Exhibit 4.4


 


Execution Copy




 





 


 


MARKWEST ENERGY PARTNERS, L.P.,


 


MARKWEST ENERGY FINANCE CORPORATION, as Issuers,


 


THE SUBSIDIARIES NAMED HEREIN, as Subsidiary Guarantors


 


AND


 


WELLS FARGO BANK, NATIONAL ASSOCIATION, as Trustee


 






 


63/4% Senior Notes due 2020


 






 


 


FIRST SUPPLEMENTAL INDENTURE


 


Dated as of November 2, 2010


 




 





 

















 


CROSS-REFERENCE TABLE*


 


	
  Trust Indenture

  Act Section

  	
   

  	
  Supplemental

  Indenture

  Section(s)

  
	
  310

  	
  (a)(1)

  	
   

  	
  8.10

  
	
   

  	
  (a)(2)

  	
   

  	
  8.10

  
	
   

  	
  (a)(3)

  	
   

  	
  N.A.

  
	
   

  	
  (a)(4)

  	
   

  	
  N.A.

  
	
   

  	
  (a)(5)

  	
   

  	
  8.10

  
	
   

  	
  (b)

  	
   

  	
  8.10

  
	
   

  	
  (c)

  	
   

  	
  N.A.

  
	
  311

  	
  (a)

  	
   

  	
  8.11

  
	
   

  	
  (b)

  	
   

  	
  8.11

  
	
   

  	
  (c)

  	
   

  	
  N.A.

  
	
  312

  	
  (a)

  	
   

  	
  3.08

  
	
   

  	
  (b)

  	
   

  	
  13.02

  
	
   

  	
  (c)

  	
   

  	
  13.02

  
	
  313

  	
  (a)

  	
   

  	
  8.06

  
	
   

  	
  (b)(1)

  	
   

  	
  N.A.

  
	
   

  	
  (b)(2)

  	
   

  	
  8.06

  
	
   

  	
  (c)

  	
   

  	
  8.06; 13.02

  
	
   

  	
  (d)

  	
   

  	
  8.06

  
	
  314

  	
  (a)

  	
   

  	
  5.03; 5.18; 13.02

  
	
   

  	
  (b)

  	
   

  	
  N.A.

  
	
   

  	
  (c)(1)

  	
   

  	
  13.04

  
	
   

  	
  (c)(2)

  	
   

  	
  13.04

  
	
   

  	
  (c)(3)

  	
   

  	
  N.A.

  
	
   

  	
  (d)

  	
   

  	
  N.A.

  
	
   

  	
  (e)

  	
   

  	
  12.05

  
	
   

  	
  (f)

  	
   

  	
  N.A.

  
	
  315

  	
  (a)

  	
   

  	
  7.01

  
	
   

  	
  (b)

  	
   

  	
  8.05; 13.02

  
	
   

  	
  (c)

  	
   

  	
  8.01

  
	
   

  	
  (d)

  	
   

  	
  8.01; 7.05

  
	
   

  	
  (e)

  	
   

  	
  7.11

  
	
  316

  	
  (a)(last sentence)

  	
   

  	
  3.11

  
	
   

  	
  (a)(1)(A)

  	
   

  	
  7.05

  
	
   

  	
  (a)(1)(B)

  	
   

  	
  7.04

  
	
   

  	
  (a)(2)

  	
   

  	
  N.A.

  
	
   

  	
  (b)

  	
   

  	
  7.07

  
	
   

  	
  (c)

  	
   

  	
  10.04

  
	
  317

  	
  (a)(1)

  	
   

  	
  7.08

  
	
   

  	
  (a)(2)

  	
   

  	
  7.09

  
	
   

  	
  (b)

  	
   

  	
  3.07

  
	
  318

  	
  (a)

  	
   

  	
  13.01

  
	
   

  	
  (b)

  	
   

  	
  N.A.

  
	
   

  	
  (c)

  	
   

  	
  13.01

  



 






N.A.
means not applicable.


*This
Cross-Reference Table is not part of this Supplemental Indenture.


 


i

















 


TABLE OF CONTENTS


 


	
  ARTICLE I APPLICATION OF SUPPLEMENTAL INDENTURE

  	
   

  	
  2

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 1.01

  	
   

  	
  Application of this Supplemental Indenture

  	
   

  	
  2

  
	
  Section 1.02

  	
   

  	
  Effect of Supplemental Indenture

  	
   

  	
  2

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  ARTICLE II DEFINITIONS AND
  INCORPORATION BY REFERENCE

  	
   

  	
  3

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 2.01

  	
   

  	
  Definitions

  	
   

  	
  3

  
	
  Section 2.02

  	
   

  	
  Other Definitions

  	
   

  	
  27

  
	
  Section 2.03

  	
   

  	
  Incorporation by Reference of Trust Indenture Act

  	
   

  	
  28

  
	
  Section 2.04

  	
   

  	
  Rules of Construction

  	
   

  	
  28

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  ARTICLE III THE NOTES

  	
   

  	
  29

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 3.01

  	
   

  	
  Forms Generally

  	
   

  	
  29

  
	
  Section 3.02

  	
   

  	
  Form of Legend for Global Notes

  	
   

  	
  29

  
	
  Section 3.03

  	
   

  	
  Title and Terms

  	
   

  	
  30

  
	
  Section 3.04

  	
   

  	
  Denominations

  	
   

  	
  30

  
	
  Section 3.05

  	
   

  	
  Execution and Authentication

  	
   

  	
  30

  
	
  Section 3.06

  	
   

  	
  Registration, Registration of Transfer and Exchange

  	
   

  	
  31

  
	
  Section 3.07

  	
   

  	
  Paying Agent to Hold Money in Trust

  	
   

  	
  33

  
	
  Section 3.08

  	
   

  	
  Holder Lists

  	
   

  	
  33

  
	
  Section 3.09

  	
   

  	
  Mutilated, Destroyed, Lost and Stolen Notes

  	
   

  	
  34

  
	
  Section 3.10

  	
   

  	
  Outstanding Notes

  	
   

  	
  34

  
	
  Section 3.11

  	
   

  	
  Treasury Notes

  	
   

  	
  34

  
	
  Section 3.12

  	
   

  	
  Payment of Interest; Interest Rights Preserved

  	
   

  	
  35

  
	
  Section 3.13

  	
   

  	
  Persons Deemed Owners

  	
   

  	
  35

  
	
  Section 3.14

  	
   

  	
  Temporary Notes

  	
   

  	
  36

  
	
  Section 3.15

  	
   

  	
  Cancellation

  	
   

  	
  36

  
	
  Section 3.16

  	
   

  	
  Computation of Interest

  	
   

  	
  36

  
	
  Section 3.17

  	
   

  	
  Global Securities

  	
   

  	
  36

  
	
  Section 3.18

  	
   

  	
  CUSIP Numbers

  	
   

  	
  36

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  ARTICLE IV REDEMPTION AND
  PREPAYMENT OF NOTES

  	
   

  	
  37

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 4.01

  	
   

  	
  Notices to Trustee 

  	
   

  	
  37

  
	
  Section 4.02

  	
   

  	
  Selection of Notes to Be Redeemed 

  	
   

  	
  37

  
	
  Section 4.03

  	
   

  	
  Notice of Redemption 

  	
   

  	
  38

  
	
  Section 4.04

  	
   

  	
  Effect of Notice of Redemption 

  	
   

  	
  39

  
	
  Section 4.05

  	
   

  	
  Deposit of Redemption Price 

  	
   

  	
  39

  
	
  Section 4.06

  	
   

  	
  Notes Redeemed in Part 

  	
   

  	
  39

  
	
  Section 4.07

  	
   

  	
  Optional Redemption 

  	
   

  	
  39

  
	
  Section 4.08

  	
   

  	
  Mandatory Redemption 

  	
   

  	
  40

  
	
  Section 4.09

  	
   

  	
  Offer to Purchase by Application of Net Proceeds 

  	
   

  	
  40

  



 


ii

















 


	
  ARTICLE V COVENANTS

  	
   

  	
  43

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 5.01

  	
   

  	
  Payment of Notes

  	
   

  	
  43

  
	
  Section 5.02

  	
   

  	
  Maintenance of Office or Agency

  	
   

  	
  43

  
	
  Section 5.03

  	
   

  	
  Compliance Certificate

  	
   

  	
  43

  
	
  Section 5.04

  	
   

  	
  Taxes

  	
   

  	
  44

  
	
  Section 5.05

  	
   

  	
  Stay, Extension and Usury Laws

  	
   

  	
  44

  
	
  Section 5.06

  	
   

  	
  Change of Control

  	
   

  	
  44

  
	
  Section 5.07

  	
   

  	
  Asset Sales

  	
   

  	
  47

  
	
  Section 5.08

  	
   

  	
  Restricted Payments

  	
   

  	
  49

  
	
  Section 5.09

  	
   

  	
  Incurrence of Indebtedness and Issuance of Disqualified
  Equity

  	
   

  	
  52

  
	
  Section 5.10

  	
   

  	
  Liens

  	
   

  	
  55

  
	
  Section 5.11

  	
   

  	
  Dividend and Other Payment Restrictions Affecting
  Subsidiaries

  	
   

  	
  56

  
	
  Section 5.12

  	
   

  	
  Transactions With Affiliates

  	
   

  	
  57

  
	
  Section 5.13

  	
   

  	
  Additional Subsidiary Guarantees

  	
   

  	
  59

  
	
  Section 5.14

  	
   

  	
  Designation of Restricted and Unrestricted Subsidiaries

  	
   

  	
  59

  
	
  Section 5.15

  	
   

  	
  Business Activities

  	
   

  	
  59

  
	
  Section 5.16

  	
   

  	
  Sale and Leaseback Transactions

  	
   

  	
  60

  
	
  Section 5.17

  	
   

  	
  Payments for Consent

  	
   

  	
  60

  
	
  Section 5.18

  	
   

  	
  Reports

  	
   

  	
  60

  
	
  Section 5.19

  	
   

  	
  Termination of Covenants

  	
   

  	
  61

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  ARTICLE VI SUCCESSORS

  	
   

  	
  62

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 6.01

  	
   

  	
  Merger, Consolidation, or Sale of Assets

  	
   

  	
  62

  
	
  Section 6.02

  	
   

  	
  Successor Entity Substituted

  	
   

  	
  64

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  ARTICLE VII DEFAULTS AND
  REMEDIES

  	
   

  	
  65

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 7.01

  	
   

  	
  Events of Default

  	
   

  	
  65

  
	
  Section 7.02

  	
   

  	
  Acceleration

  	
   

  	
  67

  
	
  Section 7.03

  	
   

  	
  Other Remedies

  	
   

  	
  67

  
	
  Section 7.04

  	
   

  	
  Waiver of Past Defaults

  	
   

  	
  68

  
	
  Section 7.05

  	
   

  	
  Control by Majority

  	
   

  	
  68

  
	
  Section 7.06

  	
   

  	
  Limitation on Suits

  	
   

  	
  68

  
	
  Section 7.07

  	
   

  	
  Rights of Holders of Notes to Receive Payment

  	
   

  	
  69

  
	
  Section 7.08

  	
   

  	
  Collection Suit by Trustee

  	
   

  	
  69

  
	
  Section 7.09

  	
   

  	
  Trustee May File Proofs of Claim

  	
   

  	
  69

  
	
  Section 7.10

  	
   

  	
  Priorities

  	
   

  	
  70

  
	
  Section 7.11

  	
   

  	
  Undertaking for Costs

  	
   

  	
  70

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  ARTICLE VIII TRUSTEE

  	
   

  	
  70

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 8.01

  	
   

  	
  Duties of Trustee

  	
   

  	
  70

  
	
  Section 8.02

  	
   

  	
  Rights of Trustee

  	
   

  	
  72

  
	
  Section 8.03

  	
   

  	
  Individual Rights of Trustee

  	
   

  	
  74

  
	
  Section 8.04

  	
   

  	
  Trustee’s Disclaimer

  	
   

  	
  74

  
	
  Section 8.05

  	
   

  	
  Notice of Defaults

  	
   

  	
  74

  
	
  Section 8.06

  	
   

  	
  Reports by Trustee to Holders of the Notes

  	
   

  	
  75

  



 


iii

















 


	
  Section 8.07

  	
   

  	
  Compensation and Indemnity

  	
   

  	
  75

  
	
  Section 8.08

  	
   

  	
  Replacement of Trustee

  	
   

  	
  76

  
	
  Section 8.09

  	
   

  	
  Successor Trustee by Merger, Etc.

  	
   

  	
  77

  
	
  Section 8.10

  	
   

  	
  Eligibility; Disqualification

  	
   

  	
  77

  
	
  Section 8.11

  	
   

  	
  Preferential Collection of Claims Against Issuers

  	
   

  	
  77

  
	
  Section 8.12

  	
   

  	
  U.S.A. Patriot Act

  	
   

  	
  78

  
	
  Section 8.13

  	
   

  	
  Force Majeure

  	
   

  	
  78

  
	
   

  	
   

  	
   

  
	
  ARTICLE IX LEGAL DEFEASANCE
  AND COVENANT DEFEASANCE

  	
   

  	
  78

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 9.01

  	
   

  	
  Option to Effect Legal Defeasance or Covenant Defeasance

  	
   

  	
  78

  
	
  Section 9.02

  	
   

  	
  Legal Defeasance and Discharge

  	
   

  	
  78

  
	
  Section 9.03

  	
   

  	
  Covenant Defeasance

  	
   

  	
  79

  
	
  Section 9.04

  	
   

  	
  Conditions to Legal Defeasance or Covenant Defeasance

  	
   

  	
  79

  
	
  Section 9.05

  	
   

  	
  Deposited Money and Government Securities to be Held in
  Trust, Other Miscellaneous Provisions

  	
   

  	
  80

  
	
  Section 9.06

  	
   

  	
  Reinstatement

  	
   

  	
  81

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  ARTICLE X AMENDMENT,
  SUPPLEMENT AND WAIVER

  	
   

  	
  82

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 10.01

  	
   

  	
  Without Consent of Holders of Notes

  	
   

  	
  82

  
	
  Section 10.02

  	
   

  	
  With Consent of Holders of Notes

  	
   

  	
  83

  
	
  Section 10.03

  	
   

  	
  Compliance with Trust Indenture Act

  	
   

  	
  84

  
	
  Section 10.04

  	
   

  	
  Revocation and Effect of Consents

  	
   

  	
  84

  
	
  Section 10.05

  	
   

  	
  Notation or Exchange of Notes

  	
   

  	
  85

  
	
  Section 10.06

  	
   

  	
  Trustee to Sign Amendments, Etc.

  	
   

  	
  85

  
	
  Section 10.07

  	
   

  	
  Effect of Supplemental Indentures

  	
   

  	
  85

  
	
   

  	
   

  	
   

  
	
  ARTICLE XI GUARANTEES

  	
   

  	
  86

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 11.01

  	
   

  	
  Guarantees

  	
   

  	
  86

  
	
  Section 11.02

  	
   

  	
  Limitation of Guarantor’s Liability

  	
   

  	
  87

  
	
  Section 11.03

  	
   

  	
  Execution and Delivery of Notations of Guarantees

  	
   

  	
  87

  
	
  Section 11.04

  	
   

  	
  Releases

  	
   

  	
  88

  
	
  Section 11.05

  	
   

  	
  “Trustee” to Include Paying Agent

  	
   

  	
  89

  
	
   

  	
   

  	
   

  
	
  ARTICLE XII SATISFACTION AND
  DISCHARGE

  	
   

  	
  89

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 12.01

  	
   

  	
  Satisfaction and Discharge

  	
   

  	
  89

  
	
  Section 12.02

  	
   

  	
  Application of Trust

  	
   

  	
  90

  
	
  Section 12.03

  	
   

  	
  Repayment of the Issuers

  	
   

  	
  91

  
	
  Section 12.04

  	
   

  	
  Reinstatement

  	
   

  	
  91

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  ARTICLE XIII MISCELLANEOUS

  	
   

  	
  91

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Section 13.01

  	
   

  	
  Notices

  	
   

  	
  91

  
	
  Section 13.02

  	
   

  	
  Communication by Holders of Notes with Other Holders of
  Notes

  	
   

  	
  93

  
	
  Section 13.03

  	
   

  	
  Certificate and Opinion as to Conditions Precedent

  	
   

  	
  93

  
	
  Section 13.04

  	
   

  	
  Statements Required in Certificate or Opinion

  	
   

  	
  94

  



 


iv

















 


	
  Section 13.05

  	
   

  	
  No Personal Liability of Directors, Officers, Employees and
  Unitholders and No Recourse Against General Partner

  	
   

  	
  94

  
	
  Section 13.06

  	
   

  	
  No Adverse Interpretation of Other Agreements

  	
   

  	
  94

  
	
  Section 13.07

  	
   

  	
  Successors

  	
   

  	
  94

  
	
  Section 13.08

  	
   

  	
  Counterpart Originals

  	
   

  	
  95

  
	
  Section 13.09

  	
   

  	
  Indenture and Notes to Be Construed in Accordance with the
  Laws of the State of New York

  	
   

  	
  95

  
	
  Section 13.10

  	
   

  	
  Provisions Required by TIA to Control

  	
   

  	
  95

  
	
  Section 13.11

  	
   

  	
  Rules by Trustee, Paying Agent and Registrar

  	
   

  	
  95

  
	
  Section 13.12

  	
   

  	
  Severability

  	
   

  	
  95

  
	
  Section 13.13

  	
   

  	
  Table of Contents, Headings, Etc.

  	
   

  	
  95

  



 


	
  Subsidiary
  Guarantors

  	
   

  	
   

  	
   

  	
  Schedule A

  
	
  Form of
  Note

  	
   

  	
   

  	
   

  	
  Exhibit A

  
	
  Form of
  Guarantee

  	
   

  	
   

  	
   

  	
  Exhibit B

  
	
  Form of
  Supplemental Indenture

  	
   

  	
   

  	
   

  	
  Exhibit C

  



 


v
















 


THIS
FIRST SUPPLEMENTAL INDENTURE (this “Supplemental Indenture”) dated as of November 2,
2010 is among MarkWest Energy Partners, L.P., a Delaware limited partnership
(the “Partnership”), MarkWest Energy Finance Corporation, a Delaware
corporation (“MarkWest Finance” and, together with the Partnership, the “Issuers”),
the Subsidiary Guarantors (as defined herein) listed on Schedule A hereto, and
Wells Fargo Bank, National Association, a national banking association, as
Trustee under the Indenture, dated the date hereof, among the Issuers, the
Subsidiary Guarantors and the Trustee (the “Base Indenture” and, as amended and
supplemented by this Supplemental Indenture, in respect of the Notes, the “Indenture”).


 


RECITALS


 


The
Issuers, the Subsidiary Guarantors and the Trustee have duly authorized,
executed and delivered the Base Indenture to provide for the issuance from time
to time of the Issuers’ debentures, notes, bonds or other evidences of
indebtedness, to be issued in one or more series unlimited as to principal
amount (herein called “Debt Securities”), which Debt Securities may be
guaranteed by each of the Subsidiary Guarantors, as the Base Indenture
provides.


 


Section 9.01
of the Base Indenture provides, among other things, that the Issuers, the
Subsidiary Guarantors and the Trustee may enter into indentures supplemental to
the Base Indenture, without the consent of any Holders of Debt Securities, to
establish the form or terms of any Debt Security as permitted by Sections 2.01
and 2.03 of the Base Indenture.


 


Pursuant
to Sections 2.01 and 2.03 of the Base Indenture, the Issuers desire to execute
this Supplemental Indenture to establish the form and terms, and to provide for
the issuance, of a series of senior notes designated as 63⁄4% Senior Notes due
2020 in an aggregate principal amount of $500,000,000 (the “Initial Notes”).


 


From
time to time subsequent to the Issue Date, the Issuers may, if permitted to do
so pursuant to the terms of the Indenture, the Initial Notes and the terms of
their other indebtedness existing on such future date, issue additional senior
notes of the same series as the Initial Notes in accordance with this
Supplemental Indenture (the “Additional Notes” and, together with the Initial
Notes, the “Notes”), pursuant to this Supplemental Indenture.


 


The
Issuers and the Subsidiary Guarantors are members of the same consolidated
group of companies. The Subsidiary Guarantors will derive direct and indirect
economic benefit from the issuance of the Notes. Accordingly, each Subsidiary
Guarantor has duly authorized the execution and delivery of this Supplemental
Indenture to provide for its full, unconditional and joint and several
Guarantee of the Notes to the extent provided in or pursuant to the Indenture.


 


This
Supplemental Indenture is subject to the provisions of the Trust Indenture Act
of 1939, as amended, that are required to be a part of this Supplemental
Indenture and shall, to the extent applicable, be governed by such provisions.


 


All
things necessary have been done to make the Notes, when executed by the Issuers
and authenticated and delivered hereunder and duly issued by the Issuers, the
valid obligations of the


 


1

















 


Issuers,
and all things necessary have been done to make the Guarantees thereof, when
the Notes have been executed by the Issuers and authenticated and delivered
hereunder and duly issued by the Issuers, the valid obligations of the
Subsidiary Guarantors.


 


All
things necessary to make this Supplemental Indenture a valid agreement of each
of the Issuers and the Subsidiary Guarantors, in accordance with its terms,
have been done.


 


NOW,
THEREFORE, THIS SUPPLEMENTAL INDENTURE WITNESSETH:


 


For
and in consideration of the premises and the purchase of the Notes by the
Holders thereof, it is mutually agreed, for the equal and proportionate benefit
of all Holders of the Notes, as follows:


 


ARTICLE I

APPLICATION OF SUPPLEMENTAL INDENTURE


 


Section 1.01           Application of this
Supplemental Indenture.


 


Notwithstanding
any other provision of this Supplemental Indenture, the provisions of this
Supplemental Indenture, including as provided in Section 1.02 below, are
expressly and solely for the benefit of the Holders of the Notes and the
Guarantees and shall not apply to any other series of Debt Securities that may
be issued hereafter under the Base Indenture. The Notes constitute a series of
Debt Securities as provided in the Base Indenture. Unless otherwise expressly
specified, references in this Supplemental Indenture to specific Article numbers
or Section numbers refer to Articles and Sections contained in this
Supplemental Indenture, and not the Base Indenture or any other document.


 


Section 1.02           Effect of Supplemental
Indenture.


 


With
respect to the Notes (and any notation of Guarantee endorsed thereon) only, the
Base Indenture shall be supplemented and amended pursuant to Section 9.01
thereof to establish the form and terms of the Notes (and any notation of
Guarantee endorsed thereon) as set forth in this Supplemental Indenture,
including as follows:


 


(a)           Definitions. Article I of the Base Indenture is deleted
and replaced in its entirety by the provisions of Article II of this
Supplemental Indenture;


 


(b)           Security Forms. Article II of the Base Indenture is
deleted and replaced in its entirety by the provisions of Article III of
this Supplemental Indenture;


 


(c)           Redemption. The provisions of Article III of the Base
Indenture are deleted and replaced in their entirety by the provisions of Article IV
of this Supplemental Indenture;


 


(d)           Covenants. The provisions of Article IV of the Base
Indenture are deleted and replaced in their entirety by the provisions of Article V
of this Supplemental Indenture;


 


2

















 


(e)           Holders’ Lists and Reports by Trustee. The provisions of Article V
of the Base Indenture are deleted in their entirety;


 


(f)            Remedies of the Trustee and Holders in Event of Default. The
provisions of Article VI of the Base Indenture are deleted and replaced in
their entirety by the provisions of Article VII of this Supplemental
Indenture;


 


(g)           The Trustee. The provisions of Article VII of the Base
Indenture are deleted and replaced in their entirety by the provisions of Article VIII
of this Supplemental Indenture;


 


(h)           The Holders. The provisions of Article VIII of the Base
Indenture are deleted in their entirety;


 


(i)            Supplemental Indentures. The provisions of Article IX
of the Base Indenture are deleted and replaced in their entirety by the
provisions of Article X of this Supplemental Indenture;


 


(j)            Consolidation, Merger, Sale of Assets. The provisions of Article X
of the Base Indenture are deleted and replaced in their entirety by the
provisions of Article VI of this Supplemental Indenture;


 


(k)           Satisfaction and Discharge; Defeasance. The provisions of Article XI
of the Base Indenture are deleted and replaced in their entirety by the
provisions of Article IX and Article XII of this Supplemental
Indenture;


 


(l)            Guarantees. The provisions of Article XIV of the Base
Indenture are deleted and replaced in their entirety by the provisions of Article XI
of this Supplemental Indenture; and


 


(m)          Miscellaneous. 
The provisions of Article XIII of the Base Indenture are deleted
and replaced in their entirety by the provisions of Article XIII of this
Supplemental Indenture:


 


To
the extent that the provisions of this Supplemental Indenture (including those
referred to in clauses (a) through (m) above) conflict with any
provision of the Base Indenture, the provisions of this Supplemental Indenture
shall govern and be controlling, solely with respect to the Notes (and any
notation of Guarantee endorsed thereon).


 


ARTICLE II

DEFINITIONS AND INCORPORATION BY REFERENCE


 


Section 2.01           Definitions.


 


“Acquired
Debt” means, with respect to any specified Person:


 


3

















 


(a)           Indebtedness
of any other Person existing at the time such other Person is merged with or
into or became a Subsidiary of such specified Person, whether or not such
Indebtedness is incurred in connection with, or in contemplation of, such other
Person merging with or into, or becoming a Subsidiary of, such specified
Person, but excluding Indebtedness that is extinguished, retired or repaid in
connection with such Person merging with or becoming a Subsidiary of such specified
Person; and


 


(b)           Indebtedness
secured by a Lien encumbering any asset acquired by such specified Person.


 


“Affiliate”
of any specified Person means any other Person directly or indirectly
controlling or controlled by or under direct or indirect common control with
such specified Person. For purposes of this definition, “control,” as used with
respect to any Person, shall mean the possession, directly or indirectly, of
the power to direct or cause the direction of the management or policies of
such Person, whether through the ownership of voting securities, by agreement
or otherwise; provided that beneficial ownership of 10% or more of the Voting
Stock of a specified Person shall be deemed to be control by the other Person;
provided, further, that any third Person which also beneficially owns 10% or
more of the Voting Stock of a specified Person shall not be deemed to be an
Affiliate of either the specified Person or the other Person merely because of
such common ownership in such specified Person. For purposes of this
definition, the terms “controlling,” “controlled by” and “under common control
with” shall have correlative meanings. Notwithstanding the preceding, the term “Affiliate”
shall not include a Restricted Subsidiary of any specified Person.


 


“Agent”
means any Registrar or Paying Agent.


 


“Asset
Sale” means:


 


(a)           the
sale, lease, conveyance or other disposition of any assets, other than
dispositions of any products, equipment or services in the ordinary course of
business; provided that the sale, lease, conveyance or other disposition of all
or substantially all of the assets of the Partnership and its Restricted
Subsidiaries taken as a whole will be governed by the provisions of Section 5.06
and/or the provisions of Article VI hereof and not by the provisions of Section 5.07;
and


 


(b)           the
issuance of Equity Interests by any of the Partnership’s Restricted
Subsidiaries or the sale by the Partnership or any of its Restricted
Subsidiaries of Equity Interests in any of its Restricted Subsidiaries.


 


Notwithstanding
the preceding, the following items shall not be deemed to be Asset Sales:


 


(a)           any
single transaction or series of related transactions that: (i) involves
assets having a fair market value of less than $15.0 million; or (ii) results
in net proceeds to the Partnership and its Restricted Subsidiaries of less than
$15.0 million;


 


4

















 


(b)           a
transfer of assets between or among the Partnership and its Restricted
Subsidiaries;


 


(c)           an
issuance or sale of Equity Interests by a Restricted Subsidiary to the
Partnership or to another Restricted Subsidiary of the Partnership;


 


(d)           a
Restricted Payment that is permitted under Section 5.08 hereof or a
Permitted Investment;


 


(e)           the
sale or other disposition of cash or Cash Equivalents, Hedging Obligations or
other financial instruments in the ordinary course of business;


 


(f)            any
trade or exchange by the Partnership or any of its Restricted Subsidiaries of
assets for properties or assets owned or held by another Person, provided that
the fair market value of the assets traded or exchanged by the Partnership or
such Restricted Subsidiary (together with any cash) is reasonably equivalent to
the fair market value of the assets (together with any cash) to be received by
the Partnership or such Restricted Subsidiary, and provided further that any
cash received must be applied in accordance with the provisions of Section 5.07
hereof;


 


(g)           surrender
or waiver of contract rights or the settlement, release or surrender of
contract, tort or other claims of any kind;


 


(h)           the
creation or perfection of a Lien that is not prohibited by Section 5.07;


 


(i)            dispositions
in connection with Permitted Liens; and


 


(j)            the
grant in the ordinary course of business of any non-exclusive license of
patents, trademarks, registrations therefor and other similar intellectual
property.


 


“Attributable
Debt” in respect of a sale and leaseback transaction means, at the time of
determination, the present value of the obligation of the lessee for net rental
payments during the remaining term of the lease included in such sale and
leaseback transaction, including any period for which such lease has been
extended or may, at the option of the lessor, be extended. Such present value
shall be calculated using a discount rate equal to the rate of interest
implicit in such transaction, determined in accordance with GAAP.


 


“Available
Cash” has the meaning assigned to such term in the Partnership Agreement, as in
effect on the Issue Date.


 


“Bankruptcy
Law” means Title 11, U.S. Code or any similar federal or state law for the
relief of debtors.


 


“Beneficial
Owner” has the meaning assigned to such term in Rule 13d-3 and Rule 13d-5
under the Exchange Act, except that in calculating the beneficial ownership of
any particular “person” (as that term is used in Section 13(d)(3) of
the Exchange Act), such “person” will be


 


5

















 


deemed
to have beneficial ownership of all securities that such “person” has the right
to acquire by conversion or exercise of other securities, whether such right is
currently exercisable or is exercisable only upon the occurrence of a
subsequent condition. The terms “Beneficially Owns” and “Beneficially Owned”
have correlative meanings.


 


“Board
of Directors” means, with respect to the Partnership, the Board of Directors of
the General Partner, or any authorized committee of such Board of Directors,
and with respect to MarkWest Finance or any other Subsidiary of the
Partnership, the Board of Directors or managing members of such Person.


 


“Board
Resolution” means a copy of a resolution certified by the Secretary or an
Assistant Secretary of the applicable Person to have been duly adopted by the
Board of Directors of such Person and to be in full force and effect on the
date of such certification, and delivered to the Trustee.


 


“Business
Day” means any day other than a Legal Holiday.


 


“Capital
Lease Obligation” means, at the time any determination thereof is to be made,
the amount of the liability in respect of a capital lease that would at that
time be required to be capitalized on a balance sheet in accordance with GAAP.


 


“Cash
Equivalents” means:


 


(a)           United
States dollars or, in an amount up to the amount necessary or appropriate to
fund local operating expenses, other currencies;


 


(b)           securities
issued or directly and fully guaranteed or insured by the United States
government or any agency or instrumentality thereof (provided that the full
faith and credit of the United States is pledged in support thereof) having
maturities of not more than one year from the date of acquisition;


 


(c)           certificates
of deposit, time deposits and eurodollar time deposits with maturities of one
year or less from the date of acquisition, bankers’ acceptances with maturities
not exceeding 365 days, demand and overnight bank deposits and other similar
types of investments routinely offered by commercial banks, in each case, with
any domestic commercial bank having a combined capital and surplus in excess of
$500.0 million and a Thomson BankWatch Rating of “B” or better or any
commercial bank of any other country that is a member of the Organization for
Economic Cooperation and Development (“OECD”) and has total assets in excess of
$500.0 million;


 


(d)           repurchase
obligations with a term of not more than seven days for underlying securities
of the types described in clauses (b) and (c) above entered into with
any financial institution meeting the qualifications specified in clause (c) above;


 


6

















 


(e)           commercial
paper having one of the two highest ratings obtainable from Moody’s or Standard &
Poor’s and in each case maturing within six months after the date of
acquisition; and


 


(f)            money
market funds at least 95% of the assets of which constitute Cash Equivalents of
the kinds described in clauses (a) through (e) of this definition.


 


“Certificated
Note” means a Note in certificated form registered in the name of the Holder
thereof and issued in accordance with Article III hereof, in substantially
the form of Exhibit A hereto, except that such Note shall not bear
the Global Note Legend and shall not have the “Schedule of Exchanges of
Interests in the Global Note” attached thereto.


 


“Change
of Control” means the occurrence of any of the following:


 


(a)           the
direct or indirect sale, lease, transfer, conveyance or other disposition
(other than by way of merger or consolidation), in one or a series of related
transactions, of all or substantially all of the properties or assets
(including Equity Interests of the Restricted Subsidiaries) of the Partnership
and its Restricted Subsidiaries taken as a whole, to any “person” (as that term
is used in Section 13(d)(3) of the Exchange Act);


 


(b)           the
adoption of a plan relating to the liquidation or dissolution of the
Partnership or the removal of the General Partner by the limited partners of
the Partnership;


 


(c)           the
consummation of any transaction (including, without limitation, any merger or
consolidation) the result of which is that any “person” (as that term is used
in Section 13(d)(3) of the Exchange Act), excluding the MarkWest
Group, becomes the Beneficial Owner, directly or indirectly, of more than 50%
of the Voting Stock of the General Partner, measured by voting power rather
than number of shares, units or the like;


 


(d)           the
consummation of any transaction (including, without limitation, any merger or
consolidation) the result of which is that any “person” (as that term is used
in Section 13(d)(3) of the Exchange Act) becomes the Beneficial Owner,
directly or indirectly, of more than 50% of the Voting Stock of the
Partnership, measured by voting power rather than number of shares, units or
the like, at a time when the Partnership still Beneficially Owns more than 50%
of the Voting Stock of the General Partner, measured by voting power rather
than number of shares, units or the like; or


 


(e)           the
first day on which a majority of the members of the Board of Directors of the
General Partner are not Continuing Directors.


 


Notwithstanding
the preceding, a conversion of the Partnership from a limited partnership to a
corporation, limited liability company or other form of entity or an exchange
of all of the outstanding limited partnership interests for capital stock in a
corporation, for member interests in a limited liability company or for Equity
Interests in such other form of entity shall not constitute a Change of
Control, so long as following such conversion or exchange the MarkWest Group
Beneficially Owns, directly or indirectly, in the aggregate more than 50% of
the Voting


 


7

















 


Stock
of such entity, or continues to Beneficially Own a sufficient percentage of
Voting Stock of such entity to elect a majority of its directors, managers,
trustees or other persons serving in a similar capacity for such entity.


 


“Code”
means the Internal Revenue Code of 1986, as amended from time to time, and the rules and
regulations thereunder, and any successor thereto.


 


“Consolidated
Cash Flow” means, with respect to any Person for any period, the Consolidated
Net Income of such Person for such period plus:


 


(a)           an
amount equal to any net loss realized by such Person and its Restricted
Subsidiaries in connection with an Asset Sale, to the extent such losses were
deducted in computing such Consolidated Net Income; plus


 


(b)           provision
for taxes based on income or profits of such Person and its Restricted
Subsidiaries for such period, to the extent that such provision for taxes was
deducted in computing such Consolidated Net Income; plus


 


(c)           the
consolidated interest expense of such Person and its Restricted Subsidiaries
for such period, whether paid or accrued (including, without limitation,
amortization of debt issuance costs and original issue discount, non-cash
interest payments, the interest component of any deferred payment obligations,
the interest component of all payments associated with Capital Lease
Obligations, imputed interest with respect to Attributable Debt, commissions,
discounts and other fees and charges incurred in respect of letter of credit or
bankers’ acceptance financings), and net of the effect of all payments, made or
received pursuant to interest-rate Hedging Obligations, to the extent that any
such expense was deducted in computing such Consolidated Net Income; plus


 


(d)           depreciation,
depletion and amortization (including amortization of goodwill and other
intangibles but excluding amortization of prepaid cash expenses that were paid
in a prior period) and other non-cash expenses (excluding any such non-cash
expense to the extent that it represents an accrual of or reserve for cash
expenses in any future period or amortization of a prepaid cash expense that
was paid in a prior period) of such Person and its Restricted Subsidiaries for
such period to the extent that such depreciation, depletion, amortization,
impairment and other non-cash expenses were deducted in computing such
Consolidated Net Income; plus


 


(e)           unrealized
non-cash losses resulting from foreign currency balance sheet adjustments
required by GAAP to the extent such losses are deducted in computing such
Consolidated Net Income; plus


 


(f)            all
extraordinary, unusual or non-recurring items of gain or loss, or revenue or
expense; minus


 


(g)           non-cash
items increasing such Consolidated Net Income for such period, other than items
that were accrued in the ordinary course of business;


 


8

















 


in
each case, on a consolidated basis and determined in accordance with GAAP.


 


Notwithstanding
the preceding, the provision for taxes based on the income or profits of, and
the depreciation, depletion and amortization and other non-cash charges of, a
Restricted Subsidiary of the Partnership shall be added to Consolidated Net
Income to compute Consolidated Cash Flow of the Partnership only to the extent
that a corresponding amount would be permitted at the date of determination to
be dividended or distributed to the Partnership by such Restricted Subsidiary
without prior approval (that has not been obtained), pursuant to the terms of
its charter and all agreements (other than the Indenture, the Notes or its
Guarantee), instruments, judgments, decrees, orders, statutes, rules and
governmental regulations applicable to that Restricted Subsidiary or its
stockholders, partners or members.


 


“Consolidated
Net Income” means, with respect to any specified Person for any period, the
aggregate of the Net Income of such Person and its Restricted Subsidiaries for
such period, on a consolidated basis, determined in accordance with GAAP; provided
that:


 


(a)           Net
Income (but not loss) of any Person that is not a Restricted Subsidiary or that
is accounted for by the equity method of accounting will be included, but only
to the extent of the amount of dividends or distributions paid in cash to the
specified Person or a Restricted Subsidiary of the Person;


 


(b)           the
Net Income of any Restricted Subsidiary shall be excluded to the extent that
the declaration or payment of dividends or similar distributions by that
Restricted Subsidiary of that Net Income is not at the date of determination
permitted without any prior governmental approval (that has not been obtained)
or, directly or indirectly, by operation of the terms of its charter or any
agreement (other than the Indenture, the Notes or its Guarantee), instrument,
judgment, decree, order, statute, rule or governmental regulation
applicable to that Restricted Subsidiary or its stockholders, partners or
members;


 


(c)           the
cumulative effect of a change in accounting principles shall be excluded;


 


(d)           unrealized
losses and gains under derivative instruments included in the determination of
Consolidated Net Income, including, without limitation, those resulting from
the application of Financial Accounting Standards Board (FASB) Accounting
Standards Codification (ASC) 815, shall be excluded; and


 


(e)           any
charges relating to any premium or penalty paid, write off of deferred finance
costs or other charges in connection with redeeming or retiring any
Indebtedness prior to its Stated Maturity shall be excluded.


 


“Consolidated
Net Tangible Assets” means, with respect to any Person at any date of
determination, the aggregate amount of total assets included in such Person’s
most recent quarterly or annual consolidated balance sheet prepared in
accordance with GAAP less applicable reserves reflected in such balance sheet,
after deducting the following amounts: (1) all current liabilities
reflected in such balance sheet, and (2) all goodwill, trademarks,
patents,


 


9

















 


unamortized
debt discounts and expenses and other like intangibles reflected in such
balance sheet.


 


“Continuing
Directors” means, as of any date of determination, any member of the Board of
Directors of the General Partner who (1) was a member of such Board of
Directors on the Issue Date or (2) was nominated for election or elected
to such Board of Directors with the approval of a majority of the Continuing
Directors who were members of such Board of Directors at the time of such
nomination or election.


 


“Corporate
Trust Office” shall be at the address of the Trustee specified in Section 13.01
hereof or such other address as to which the Trustee may give notice to the
Issuers.


 


“Credit
Agreement” means that certain Amended and Restated Credit Agreement, dated July 1,
2010, among the Partnership, the banks parties thereto and Wells Fargo Bank,
National Association, as administrative agent, consisting of a revolver loan,
including any related notes, guarantees, collateral documents, instruments and
agreements executed in connection therewith, and in each case as amended,
restated, modified, renewed, refunded, replaced or refinanced in whole or in
part from time to time.


 


“Credit
Facilities” means, with respect to the Partnership, MarkWest Finance or any
Restricted Subsidiary, one or more credit facilities or commercial paper
facilities, including the Credit Agreement, providing for revolving credit
loans, term loans, receivables financing (including through the sale of
receivables to lenders or to special purpose entities formed to borrow from
lenders against such receivables) or letters of credit, in each case, as
amended, restated, modified, renewed, refunded, replaced or refinanced in whole
or in part from time to time.


 


“Debt
Security” or “Debt Securities” has the meaning stated in the first recital of
this Supplemental Indenture.


 


“Default”
means any event that is, or with the passage of time or the giving of notice or
both would be, an Event of Default.


 


“Depositary”
means, with respect to the Notes issuable or issued in whole or in part in
global form, the Person specified in Section 3.06 hereof as the Depositary
with respect to the Notes, and any and all successors thereto appointed as
depositary hereunder and having become such pursuant to the applicable provision
of the Indenture.


 


“Disqualified
Equity” means any Equity Interest that, by its terms (or by the terms of any
security into which it is convertible, or for which it is exchangeable, in each
case at the option of the holder thereof), or upon the happening of any event,
matures or is mandatorily redeemable, pursuant to a sinking fund obligation or
otherwise, or redeemable at the option of the holder thereof, in whole or in
part, on or prior to the date that is 91 days after the date on which the Notes
mature. Notwithstanding the preceding sentence, any Equity Interest that would
constitute Disqualified Equity solely because the holders thereof have the
right to require the Partnership or any of its Restricted Subsidiaries to
repurchase such Equity Interest upon the occurrence of a


 


10

















 


change
of control or an asset sale shall not constitute Disqualified Equity if the
terms of such Equity Interest provide that the Partnership or Restricted
Subsidiary may not repurchase or redeem any such Equity Interest pursuant to
such provisions unless such repurchase or redemption complies with Section 5.08
hereof.


 


“Domestic
Subsidiary” means any Restricted Subsidiary of the Partnership that was formed
under the laws of the United States or any state of the United States or the
District of Columbia.


 


“Equity
Interests” means:


 


(a)           in
the case of a corporation, corporate stock;


 


(b)           in
the case of an association or business entity, any and all shares, interests,
participations, rights or other equivalents (however designated) of corporate
stock;


 


(c)           in
the case of a partnership or limited liability company, partnership or
membership interests (whether general or limited);


 


(d)           any
other interest or participation that confers on a Person the right to receive a
share of the profits and losses of, or distributions of assets of, the issuing
Person; and


 


(e)           all
warrants, options or other rights to acquire any of the interests described in
clauses (a) through (d) above (but excluding any debt security that
is convertible into, or exchangeable for, any of the interests described in
clauses (a) through (d) above).


 


“Equity
Offering” means any public or private sale for cash of Equity Interests of the
Partnership (excluding sales made to any Restricted Subsidiary and excluding
sales of Disqualified Equity) after the Issue Date; provided that a private
placement of Equity Interests will not be deemed an Equity Offering unless net
cash proceeds of at least $10.0 million are received.


 


“Exchange
Act” means the Securities Exchange Act of 1934, as amended.


 


“Existing
Indebtedness” means the aggregate principal amount of Indebtedness of the
Partnership and its Restricted Subsidiaries in existence on the Issue Date.


 


The
term “fair market value” means the value that would be paid by a willing buyer
to an unaffiliated willing seller in a transaction not involving distress or
necessity of either party, determined in good faith by the Board of Directors
of the General Partner in the case of amounts of $30.0 million or more and
otherwise by an Officer of the General Partner.


 


“Fixed
Charge Coverage Ratio” means, with respect to any specified Person for any
four-quarter reference period, the ratio of the Consolidated Cash Flow of such
Person for such period to the Fixed Charges of such Person for such period. In
the event that the specified Person or any of its Restricted Subsidiaries
incurs, assumes, guarantees, repays, redeems, defeases or otherwise


 


11

















 


retires
any Indebtedness (other than revolving credit borrowings not constituting a
permanent commitment reduction) or issues, repurchases or redeems Disqualified
Equity subsequent to the commencement of the period for which the Fixed Charge
Coverage Ratio is being calculated but prior to the date on which the event for
which the calculation of the Fixed Charge Coverage Ratio is made (the “Calculation
Date”), then the Fixed Charge Coverage Ratio shall be calculated giving pro
forma effect to such incurrence, assumption, guarantee, repayment, redemption,
defeasance or other retirement of Indebtedness, or such issuance, repurchase or
redemption of Disqualified Equity, and the application of the net proceeds
thereof as if the same had occurred at the beginning of the applicable
four-quarter reference period.


 


In
addition, for purposes of calculating the Fixed Charge Coverage Ratio:


 


(a)           acquisitions
that have been made by the specified Person or any of its Restricted
Subsidiaries, including through mergers, consolidations or otherwise (including
acquisitions of assets used in a Permitted Business), and including in each
case any related financing transactions (including repayment of Indebtedness)
during the four-quarter reference period or subsequent to such reference period
and on or prior to the Calculation Date, will be given pro forma effect as if
they had occurred on the first day of the four-quarter reference period,
including any Consolidated Cash Flow and any pro forma expense and cost
reductions that have occurred or are reasonably expected to occur, in the
reasonable judgment of the chief financial or accounting officer of the
Partnership (regardless of whether those cost savings or operating improvements
could then be reflected in pro forma financial statements in accordance with
Regulation S-X promulgated under the Securities Act or any other regulation or
policy of the SEC related thereto);


 


(b)           the
Consolidated Cash Flow attributable to discontinued operations, as determined
in accordance with GAAP, and operations or businesses disposed of prior to the
Calculation Date, shall be excluded;


 


(c)           the
Fixed Charges attributable to discontinued operations, as determined in
accordance with GAAP, and operations or businesses disposed of prior to the
Calculation Date, shall be excluded, but only to the extent that the
obligations giving rise to such Fixed Charges will not be obligations of the
specified Person or any of its Restricted Subsidiaries following the
Calculation Date;


 


(d)           interest
on outstanding Indebtedness of the specified Person or any of its Restricted
Subsidiaries as of the last day of the four-quarter reference period shall be
deemed to have accrued at a fixed rate per annum equal to the rate of interest
on such Indebtedness in effect on such last day after giving effect to any
Hedging Obligation then in effect; and


 


(e)           if
interest on any Indebtedness incurred by the specified Person or any of its
Restricted Subsidiaries on such date may optionally be determined at an
interest rate based upon a factor of a prime or similar rate, a eurocurrency
interbank offered rate or other rates, then the interest rate in effect on the
last day of the four-quarter reference period will be deemed to have been in
effect during such period.


 


12
















 


“Fixed
Charges” means, with respect to any Person for any period, the sum, without
duplication, of:


 


(a)           the
consolidated interest expense of such Person and its Restricted Subsidiaries
for such period, whether paid or accrued, including, without limitation,
amortization of debt issuance costs and original issue discount, non-cash
interest payments, the interest component of any deferred payment obligations,
the interest component of all payments associated with Capital Lease
Obligations, imputed interest with respect to Attributable Debt, commissions,
discounts, and other fees and charges incurred in respect of letter of credit
or bankers’ acceptance financings, and net of the effect of all payments made
or received pursuant to interest-rate Hedging Obligations; plus


 


(b)           the
consolidated interest expense of such Person and its Restricted Subsidiaries
that was capitalized during such period; plus


 


(c)           any
interest expense on Indebtedness of another Person that is guaranteed by such
Person or one of its Restricted Subsidiaries or secured by a Lien on assets of
such Person or one of its Restricted Subsidiaries, whether or not such
guarantee or Lien is called upon; plus


 


(d)           all
dividends, whether paid or accrued and whether or not in cash, on any series of
Disqualified Equity of such Person or any of its Restricted Subsidiaries, other
than dividends on Equity Interests payable solely in Equity Interests of the
Partnership (other than Disqualified Equity) or to the Partnership or a
Restricted Subsidiary of the Partnership;


 


in
each case, on a consolidated basis and in accordance with GAAP.


 


“Foreign
Subsidiary” means any Restricted Subsidiary of the Partnership that (a) is
not a Domestic Subsidiary and (b) has 50% or more of its assets located
outside the United States or any territory thereof.


 


“GAAP”
means generally accepted accounting principles in the United States, which are
in effect from time to time.


 


“General
Partner” means MarkWest Energy GP, L.L.C., a Delaware limited liability
company, and its successors and permitted assigns as general partner of the
Partnership.


 


“Global
Note Legend” means the legend set forth in Section 3.02, which is required
to be placed on all Global Notes issued under the Indenture.


 


“Global
Note” means a  Note in global form registered
in the name of the Depositary or its nominee and issued in accordance with Article III
hereof, in substantially the form of Exhibit A hereto, bearing the
Global Note Legend and having the “Schedule of Exchanges of Interests in the
Global Note” attached thereto.


 


The
term “guarantee” means a guarantee, other than by endorsement of negotiable
instruments for collection in the ordinary course of business, direct or
indirect, in any manner,


 


13

















 


including,
without limitation, by way of a pledge of assets, or through letters of credit
or reimbursement, “claw-back,” “make-well,” or “keep-well” agreements in
respect thereof, of all or any part of any Indebtedness. The term “guarantee”
used as a verb has a corresponding meaning. 
The term “guarantor” shall mean any Person providing a guarantee of any
obligation.


 


“Guarantee”
means, individually and collectively, the guarantees given by the Subsidiary
Guarantors pursuant to Article XI hereof, including a notation in the
Notes substantially in the form attached hereto as Exhibit B.


 


“Guarantor
Subordinated Obligation” means, with respect to a Subsidiary Guarantor, any
Indebtedness or other Obligations of such Subsidiary Guarantor (whether
outstanding on the Issue Date or thereafter incurred) which are expressly
subordinate in right of payment to the Obligations of such Subsidiary Guarantor
under its Guarantee pursuant to a written agreement.


 


“Hedging
Obligations” means, with respect to any Person, the obligations of such Person
under interest rate and commodity price swap agreements, interest rate and
commodity price cap agreements, interest rate and commodity price collar
agreements and foreign currency and commodity price exchange agreements,
options or futures contracts or other similar agreements or arrangements or
Hydrocarbon hedge contracts or Hydrocarbon forward sales contracts, in each
case designed to protect such Person against fluctuations in interest rates,
foreign exchange rates, or commodities prices.


 


“Holder,”
“Holder of Notes” or other similar terms means the Person in whose name a Note
is registered in the Register (as defined in Section 3.06).


 


“Hydrocarbons”
means crude oil, natural gas, casinghead gas, drip gasoline, natural gasoline,
condensate, distillate, liquid hydrocarbons, gaseous hydrocarbons and all
constituents, elements or compounds thereof and products refined or processed
therefrom.


 


“Indebtedness”
means, with respect to any specified Person, any indebtedness of such Person,
whether or not contingent:


 


(a)           in
respect of borrowed money;


 


(b)           evidenced
by bonds, notes, debentures or similar instruments or letters of credit (or
reimbursement agreements in respect thereof);


 


(c)           in
respect of bankers’ acceptances;


 


(d)           representing
Capital Lease Obligations;


 


(e)           representing
all Attributable Debt of such Person in respect of any sale and leaseback
transactions not involving a Capital Lease Obligation;


 


14

















 


(f)            representing
the balance deferred and unpaid of the purchase price of any property, except
any such balance that constitutes an accrued expense or trade payable incurred
in the ordinary course of business;


 


(g)           representing
Disqualified Equity; or


 


(h)           representing
any Hedging Obligations;


 


if
and to the extent any of the preceding items (other than the item referred to
in clause (e), letters of credit, Disqualified Equity and Hedging Obligations)
would appear as a liability upon a balance sheet of the specified Person
prepared in accordance with GAAP. In addition, the term “Indebtedness” includes
all Indebtedness of others secured by a Lien on any asset of the specified
Person (whether or not such Indebtedness is assumed by the specified Person)
and, to the extent not otherwise included, the guarantee by such Person of any
Indebtedness of any other Person, provided that a guarantee otherwise permitted
by the Indenture to be incurred by the Partnership or any of its Restricted
Subsidiaries of Indebtedness incurred by the Partnership or a Restricted
Subsidiary in compliance with the terms of the Indenture shall not constitute a
separate incurrence of Indebtedness.


 


The
amount of any Indebtedness outstanding as of any date shall be:


 


(a)           the
accreted value thereof, in the case of any Indebtedness issued with original
issue discount;


 


(b)           in
the case of any Hedging Obligation, the termination value of the agreement or
arrangement giving rise to such Hedging Obligation that would be payable by
such Person at such date;


 


(c)           in
the case of any letter of credit, the maximum potential liability thereunder;
and


 


(d)           the
principal amount thereof, together with any interest thereon that is more than
30 days past due, in the case of any other Indebtedness.


 


For
purposes of clause (g) of the first paragraph of this definition,
Disqualified Equity shall be valued at the maximum fixed redemption, repayment
or repurchase price, which shall be calculated in accordance with the terms of
such Disqualified Equity as if such Disqualified Equity were repurchased on any
date on which Indebtedness shall be required to be determined pursuant to the
Indenture; provided, however, that if such Disqualified Equity is not then
permitted by its terms to be redeemed, repaid or repurchased, the redemption,
repayment or repurchase price shall be the book value of such Disqualified
Equity. The amount of Indebtedness of any Person at any date shall be the
outstanding balance at such date of all unconditional Obligations as described
above and the maximum liability of any guarantees at such date; provided that
for purposes of calculating the amount of any non-interest bearing or other
discount security, such Indebtedness shall be deemed to be the principal amount
thereof that would be shown on the balance sheet of the issuer thereof dated
such date prepared in


 


15

















 


accordance
with GAAP, but that such security shall be deemed to have been incurred only on
the date of the original issuance thereof.


 


“Interest
Payment Date” means Stated Maturity of an installment of interest on the Notes.


 


“Investment
Grade Rating” means a rating equal to or higher than Baa3 (or the equivalent)
by Moody’s and BBB- (or the equivalent) by Standard & Poor’s.


 


“Investments”
means, with respect to any Person, all investments by such Person in other
Persons (including Affiliates) in the forms of direct or indirect loans
(including guarantees of Indebtedness or other Obligations), advances (other
than advances to customers in the ordinary course of business that are recorded
as accounts receivable on the balance sheet of the lender and commission,
moving, travel and similar advances to officers and employees made in the
ordinary course of business) or capital contributions, purchases or other
acquisitions for consideration of Indebtedness, Equity Interests or other
securities, together with all items that are or would be classified as
investments on a balance sheet prepared in accordance with GAAP.  For purposes of the definition of “Unrestricted
Subsidiary,” the definition of “Restricted Payment” and the covenant in Section 5.08
hereof, (1) the term “Investment” shall include the portion (proportionate
to the Partnership’s Equity Interest in such Subsidiary) of the fair market
value of the net assets of any Subsidiary of the Partnership or any of its
Restricted Subsidiaries at the time that such Subsidiary is designated an
Unrestricted Subsidiary; provided, however, that upon a redesignation of such
Subsidiary as a Restricted Subsidiary, the Partnership or such Restricted
Subsidiary shall be deemed to continue to have a permanent “Investment” in such
Subsidiary at the time immediately before the effectiveness of such
redesignation less the portion (proportionate to the Partnership’s or such
Restricted Subsidiary’s Equity Interest in such Subsidiary) of the fair market
value of the net assets of such Subsidiary at the time of such redesignation,
and (2) any property transferred to or from an Unrestricted Subsidiary
shall be valued at its fair market value at the time of such transfer, in each
case as determined in good faith by the Board of Directors of the General
Partner. If the Partnership or any Restricted Subsidiary of the Partnership
sells or otherwise disposes of any Equity Interests of any direct or indirect Restricted
Subsidiary of the Partnership such that, after giving effect to any such sale
or disposition, such Person is no longer a Restricted Subsidiary of the
Partnership, the Partnership shall be deemed to have made an Investment on the
date of any such sale or disposition equal to the fair market value of the
Equity Interests of such Restricted Subsidiary not sold or disposed of.


 


“Issue
Date” means November 2, 2010.


 


“Issuer
Order” means a written request or order signed on behalf of each Issuer by an
Officer thereof and delivered to the Trustee.


 


“Joint
Venture” means any Person that is not a direct or indirect Subsidiary of the
Partnership in which the Partnership or any of its Restricted Subsidiaries
makes any Investment.


 


16

















 


“Legal
Holiday” means a Saturday, a Sunday or a day on which banking institutions in
the City of Denver, Colorado, Dallas, Texas or New York, New York or at a place
of payment are authorized by law, regulation or executive order to remain
closed. If a payment date is a Legal Holiday at a place of payment, payment may
be made at that place on the next succeeding day that is not a Legal Holiday,
and no interest shall accrue for the intervening period.


 


“Lien”
means, with respect to any asset, any mortgage, lien (statutory or otherwise),
pledge, charge, security interest, hypothecation, assignment for security,
claim, preference, priority or encumbrance of any kind in respect of such
asset, whether or not filed, recorded or otherwise perfected under applicable
law, including any conditional sale or other title retention agreement or any
lease in the nature thereof, any option or other agreement to grant a security
interest in and any filing of or agreement to give any financing statement under
the Uniform Commercial Code (or equivalent statute) of any jurisdiction other
than a precautionary financing statement respecting a lease not intended as a
security agreement.


 


“Make
Whole Amount” means, with respect to any Note at any redemption date, the
excess, if any, of (1) an amount equal to the present value of (a) the
redemption price of such Note at November 1, 2015 plus (b) the
remaining scheduled interest payments on the Notes to be redeemed to November 1,
2015 (other than interest accrued to the redemption date), computed using a
discount rate equal to the Treasury Rate plus 50 basis points, over (2) the
aggregate principal amount of the Notes to be redeemed.


 


“MarkWest
Group” means, collectively, the Partnership and each Person which is a direct
or indirect Subsidiary of the Partnership.


 


“Moody’s”
means Moody’s Investors Service, Inc. or any successor to the rating
agency business thereof.


 


“Net
Income” means, with respect to any Person, the consolidated net income (loss)
of such Person and its Restricted Subsidiaries, determined in accordance with
GAAP and before any reduction in respect of preferred stock dividends,
excluding, however:


 


(a)           the
aggregate gain (but not loss in excess of such aggregate gain), together with
any related provision for taxes on such gain, realized in connection with:


 


(i)            any Asset Sale; or


 


(ii)           the disposition of any securities by such Person or any of
its Restricted Subsidiaries or the extinguishment of any Indebtedness of such
Person or any of its Restricted Subsidiaries; and


 


(b)           any
extraordinary gain (but not loss), together with any related provision for
taxes on such extraordinary gain (but not loss).


 


“Net
Proceeds” means, with respect to any Asset Sale or sale of Equity Interests,
the aggregate proceeds received by the Partnership or any of its Restricted
Subsidiaries in cash or


 


17

















 


Cash
Equivalents in respect of any Asset Sale or sale of Equity Interests
(including, without limitation, any cash received upon the sale or other
disposition of any non-cash consideration received in any such sale), net of,
without duplication, (1) the direct costs relating to such Asset Sale or
sale of Equity Interests, including, without limitation, brokerage commissions
and legal, accounting and investment banking fees, sales commissions, recording
fees, title transfer fees, and any relocation expenses incurred as a result
thereof, (2) taxes paid or payable as a result thereof, in each case after
taking into account any available tax credits or deductions and any tax sharing
arrangements and amounts required to be applied to the repayment of
Indebtedness secured by a Lien on the asset or Equity Interests that were the
subject of such Asset Sale or sale of Equity Interests, (3) all
distributions and payments required to be made to minority interest holders in
Restricted Subsidiaries as a result of such Asset Sale and (4) any amounts
to be set aside in any reserve established in accordance with GAAP or any
amount placed in escrow, in either case for adjustment in respect of the sale
price of such asset or Equity Interests or for liabilities associated with such
Asset Sale or sale of Equity Interests and retained by the Partnership or any
of its Restricted Subsidiaries until such time as such reserve is reversed or
such escrow arrangement is terminated, in which case Net Proceeds shall include
only the amount of the reserve so reversed or the amount returned to the
Partnership or its Restricted Subsidiaries from such escrow arrangement, as the
case may be.


 


“Non-Recourse
Debt” means Indebtedness as to which:


 


(a)           neither
the Partnership nor any of its Restricted Subsidiaries (i) provides credit
support of any kind (including any undertaking, agreement or instrument that
would constitute Indebtedness), (ii) is directly or indirectly liable as a
guarantor or otherwise, or (iii) constitutes the lender of such
Indebtedness;


 


(b)           no
default with respect to which (including any rights that the holders thereof
may have to take enforcement action against an Unrestricted Subsidiary) would
permit upon notice, lapse of time or both any holder of any other Indebtedness
(other than the Notes) of the Partnership or any of its Restricted Subsidiaries
to declare a default on such other Indebtedness or cause the payment thereof to
be accelerated or payable prior to its Stated Maturity; and


 


(c)           as
to which the lenders have been notified in writing that they will not have any
recourse to the stock or assets of the Partnership or any of its Restricted
Subsidiaries, except as contemplated by clause (o) of the definition of “Permitted
Liens.”


 


“Note
Custodian” means the Trustee, as custodian with respect to the Notes in global
form, or any successor entity thereto.


 


“Obligations”
means any principal, interest, penalties, fees, indemnifications, reimbursement
obligations, damages and other liabilities payable under the documentation
governing any Indebtedness.


 


18

















 


“Officer”
means, with respect to any Person, the Chairman of the Board, the Chief
Executive Officer, the President, the Chief Operating Officer, the Chief
Financial Officer, the Chief Accounting Officer, the Treasurer, any Assistant
Treasurer, the Controller, the Secretary or any Vice President of such Person
(or, with respect to the Partnership, so long as it remains a partnership, the
General Partner).


 


“Officers’
Certificate” means a certificate signed on behalf of each of the Partnership
and MarkWest Finance by two of its Officers, one of whom must be the principal
executive officer, the principal financial officer or the principal accounting
officer of such Person, that meets the requirements of Section 13.04
hereof.


 


“Operating
Company” means MarkWest Energy Operating Company, L.L.C., a Delaware limited
liability company, and its successors.


 


“Opinion
of Counsel” means an opinion from legal counsel who is reasonably acceptable to
the Trustee, that meets the requirements of Section 13.04 hereof.  The counsel may be an employee of or counsel
to the Partnership, MarkWest Finance or the General Partner (or any Subsidiary
Guarantor, if applicable), any Subsidiary of the Partnership or the Trustee.


 


“Partnership”
means MarkWest Energy Partners, L.P., a Delaware limited partnership, and its
successors.


 


“Partnership
Agreement” means the Third Amended and Restated Agreement of Limited
Partnership of MarkWest Energy Partners, L.P., dated as of February 21,
2008, as such may be amended, modified or supplemented from time to time.


 


“Permitted
Business” means either (1) gathering, transporting, treating, processing,
marketing or otherwise handling Hydrocarbons, or activities or services
reasonably related or ancillary thereto including entering into Hedging
Obligations to support these businesses, or (2) any other business that
generates gross income that constitutes “qualifying income” under Section 7704(d) of
the Code.


 


“Permitted
Business Investments” means Investments by the Partnership or any of its
Restricted Subsidiaries in any Unrestricted Subsidiary of the Partnership or in
any Joint Venture, provided that:


 


(a)           either
(i) at the time of such Investment and immediately thereafter, the
Partnership could incur $1.00 of additional Indebtedness under Section 5.09(a) or
(ii) such Investment does not exceed the aggregate amount of Incremental
Funds (as defined in Section 5.08) not previously expended at the time of
making such Investment;


 


(b)           if
such Unrestricted Subsidiary or Joint Venture has outstanding Indebtedness at
the time of such Investment, either (i) all such Indebtedness is
Non-Recourse Debt or (ii) it is Indebtedness of such Unrestricted
Subsidiary or Joint Venture that could, at the time such Investment is made
and, if later, at the time any such Indebtedness is incurred, be


 


19

















 


incurred
by the Partnership and its Restricted Subsidiaries in accordance with the
limitation on Indebtedness set forth in Section 5.09(a); and


 


(c)           such
Unrestricted Subsidiary’s or Joint Venture’s activities are not outside the scope
of the Permitted Business.


 


“Permitted
Investments” means:


 


(a)           any
Investment in, or that results in the creation of, any Restricted Subsidiary of
the Partnership;


 


(b)           any
Investment in the Partnership or in a Restricted Subsidiary of the Partnership
(excluding redemptions, purchases, acquisitions or other retirements of Equity
Interests in the Partnership but including purchases of its Notes);


 


(c)           any
Investment in cash or Cash Equivalents;


 


(d)           any
Investment by the Partnership or any Restricted Subsidiary of the Partnership
in a Person if as a result of such Investment:


 


(i)            such Person becomes a Restricted Subsidiary of the
Partnership; or


 


(ii)           such Person is merged, consolidated or amalgamated with or
into, or transfers or conveys substantially all of its assets to, or is
liquidated into, the Partnership or a Restricted Subsidiary of the Partnership;


 


(e)           any
Investment made as a result of the receipt of consideration consisting of other
than cash or Cash Equivalents from an Asset Sale that was made pursuant to and
in compliance with Section 5.07, including pursuant to clause (f) of
the items deemed not to be Asset Sales in the definition of that term;


 


(f)            any
Investment in a Person solely in exchange for the issuance of Equity Interests
(other than Disqualified Equity) of the Partnership;


 


(g)           Investments
in stock, obligations or securities received in settlement of debts owing to
the Partnership or any of its Restricted Subsidiaries as a result of bankruptcy
or insolvency proceedings or upon the foreclosure, perfection or enforcement of
any Lien in favor of the Partnership or any such Restricted Subsidiary, in each
case as to debt owing to the Partnership or any such Restricted Subsidiary that
arose in the ordinary course of business of the Partnership or any such
Restricted Subsidiary;


 


(h)           any
Investment in Hedging Obligations permitted to be incurred under Section 5.09
hereof; and


 


(i)            other
Investments in any Person engaged in a Permitted Business (other than an
Investment in an Unrestricted Subsidiary) having an aggregate fair market value


 


20

















 


(measured
on the date each such Investment was made and without giving effect to
subsequent changes in value), when taken together with all other Investments
made pursuant to this clause (i) since the Issue Date and existing at the
time of the Investment, which is the subject of the determination, was made,
not to exceed the greater of (i) $60.0 million and (ii) 2.5% of
Consolidated Net Tangible Assets.


 


“Permitted
Liens” means:


 


(a)           Liens
securing Indebtedness under any of the Credit Facilities;


 


(b)           Liens
in favor of the Partnership or any of its Restricted Subsidiaries;


 


(c)           any
interest or title of a lessor in the property subject to a Capital Lease Obligation;


 


(d)           Liens
on property of a Person existing at the time such Person is merged with or into
or consolidated with the Partnership or any Restricted Subsidiary of the
Partnership, provided that such Liens were in existence prior to, and were not
obtained in contemplation of, such merger or consolidation and do not extend to
any assets other than those of the Person merged into or consolidated with the
Partnership or such Restricted Subsidiary;


 


(e)           Liens
on property existing at the time of acquisition thereof by the Partnership or
any Restricted Subsidiary of the Partnership, provided that such Liens were in
existence prior to, and were not obtained in contemplation of, such acquisition
and relate solely to such property, accessions thereto and the proceeds
thereof;


 


(f)            Liens
to secure the performance of tenders, bids, leases, statutory obligations,
surety or appeal bonds, government contracts, performance bonds or other
obligations of a like nature incurred in the ordinary course of business;


 


(g)           Liens
on any property or asset acquired, constructed or improved by the Partnership
or any Restricted Subsidiary, which (a) are in favor of the seller of such
property or asset, in favor of the Person constructing or improving such
property or asset, or in favor of the Person that provided the funding for the
acquisition, construction or improvement of such property or asset, (b) are
created within 360 days after the date of acquisition, construction or
improvement, (c) secure the purchase price or construction or improvement
cost, as the case may be, of such property or asset in an amount not to exceed
the lesser of (i) the cost to the Partnership and its Restricted
Subsidiaries of such acquisition, construction or improvement of such asset or
property and (ii) 100% of the fair market value of such acquisition,
construction or improvement of such property or asset, and (d) are limited
to the asset or property so acquired, constructed or improved (including
proceeds thereof, accessions thereto and upgrades thereof);


 


(h)           Liens
to secure performance of Hedging Obligations of the Partnership or a Restricted
Subsidiary;


 


(i)            Liens
existing on the Issue Date;


 


21

















 


(j)            Liens
arising under operating agreements, joint venture agreements, partnership
agreements, construction agreements, oil and gas leases, farmout agreements,
division orders, agreements for the purchase, gathering, processing, sale,
transportation or exchange of Hydrocarbons, unitization and pooling declarations
and agreements, area of mutual interest agreements and other agreements arising
in the ordinary course of the Partnership’s or any Restricted Subsidiary’s
business that are customary in the Permitted Business;


 


(k)           Liens
securing the Obligations of the Issuers under the Notes and the Indenture and
of the Subsidiary Guarantors under the Guarantees;


 


(l)            Liens
upon specific items of inventory, receivables or other goods or proceeds of the
Partnership or any of its Restricted Subsidiaries securing such Person’s
Obligations in respect of bankers’ acceptances or receivables securitizations
issued or created for the account of such Person to facilitate the purchase,
shipment or storage of such inventory, receivables or other goods or proceeds
and permitted by Section 5.09 hereof;


 


(m)          Liens
securing any Indebtedness equally and ratably with all Obligations due under
the Notes or any Guarantee pursuant to a contractual covenant that limits Liens
in a manner substantially similar to Section 5.10 hereof;


 


(n)           Liens
on and pledges of the Equity Interests of any Unrestricted Subsidiary or any
Joint Venture owned by the Partnership or any Restricted Subsidiary of the
Partnership to the extent securing Non-Recourse Debt or other Indebtedness of
such Unrestricted Subsidiary or Joint Venture;


 


(o)           Liens
incurred in the ordinary course of business of the Partnership or any
Restricted Subsidiary of the Partnership, provided that, after giving effect to
any such incurrence, the aggregate principal amount of all Indebtedness then
outstanding and secured by any Liens incurred pursuant to this clause (o) does
not exceed the greater of $60.0 million or 2.5% of the Consolidated Net
Tangible Assets of the Partnership; and


 


(p)           any
Lien renewing, extending, refinancing or refunding a Lien permitted by clauses (a) through
(o) above; provided, however, that (i) the principal amount of
Indebtedness secured by such Lien does not exceed the principal amount of such
Indebtedness outstanding immediately prior to the renewal, extension, refinancing
or refunding of such Lien plus all accrued interest on the Indebtedness secured
thereby and the amount of all fees, expenses and premiums incurred in
connection therewith, and (ii) no assets encumbered by any such Lien other
than the assets permitted to be encumbered immediately prior to such renewal,
extension, refinancing or refunding are encumbered thereby.


 


“Permitted
Refinancing Indebtedness” means any Indebtedness of the Partnership or any of
its Restricted Subsidiaries issued in exchange for, or the net proceeds of
which are used to extend, refinance, renew, replace, defease or refund other
Indebtedness of the Partnership or any of its Restricted Subsidiaries (other
than intercompany Indebtedness); provided that:


 


22

















 


(a)           the
principal amount of such Permitted Refinancing Indebtedness does not exceed the
principal amount of, plus accrued interest on, the Indebtedness so extended,
refinanced, renewed, replaced, defeased or refunded (plus the amount of
necessary fees and expenses incurred in connection therewith and any premiums
paid on the Indebtedness so extended, refinanced, renewed, replaced, defeased
or refunded);


 


(b)           such
Permitted Refinancing Indebtedness has a final maturity date no earlier than
the final maturity date of and has a Weighted Average Life to Maturity equal to
or greater than the Weighted Average Life to Maturity of, the Indebtedness
being extended, refinanced, renewed, replaced, defeased or refunded;


 


(c)           if
the Indebtedness being extended, refinanced, renewed, replaced, defeased or
refunded is subordinated in right of payment to the Notes or the Guarantees,
such Permitted Refinancing Indebtedness is subordinated in right of payment to
the Notes or the Guarantees, as the case may be, on terms at least as favorable
to the Holders of Notes as those contained in the documentation governing the
Indebtedness being extended, refinanced, renewed, replaced, defeased or
refunded; and


 


(d)           such
Indebtedness is not incurred (other than by way of a guarantee) by a Restricted
Subsidiary (other than MarkWest Finance) if the Partnership is the issuer or
other primary obligor on the Indebtedness being extended, refinanced, renewed,
replaced, defeased or refunded.


 


“Person”
means any individual, corporation, partnership, joint venture, association,
joint-stock company, trust, unincorporated organization, limited liability
company or government or any agency or political subdivision thereof or any
other entity.


 


“Prospectus”
means the prospectus of the Issuers dated October 19, 2010 relating to the
offering of the Initial Notes.


 


“Rating
Agency” means each of Standard & Poor’s and Moody’s, or if Standard &
Poor’s or Moody’s or both shall not make a rating on the Notes publicly
available, a nationally recognized statistical rating agency or agencies, as
the case may be, selected by the Issuers (as certified by a resolution of the
Board of Directors of the General Partner) which shall be substituted for
Standard & Poor’s or Moody’s, or both, as the case may be.


 


“Reporting
Default” means a Default described in Section 7.01(d).


 


“Responsible
Officer,” when used with respect to the Trustee, means the officer in the
Corporate Trust Department of the Trustee having direct responsibility for
administration of the Indenture.


 


“Restricted
Investment” means an Investment other than a Permitted Investment or a
Permitted Business Investment.


 


23

















 


“Restricted
Subsidiary” of a Person means any Subsidiary of the referenced Person that is
not an Unrestricted Subsidiary. Notwithstanding anything in the Indenture to
the contrary, each of MarkWest Finance and the Operating Company shall be a
Restricted Subsidiary of the Partnership.


 


“SEC”
means the Securities and Exchange Commission.


 


“Securities
Act” means the Securities Act of 1933, as amended.


 


“Significant
Subsidiary” means any Subsidiary that would be a “significant subsidiary” as
defined in Article 1, Rule 1-02 of Regulation S-X, promulgated
pursuant to the Securities Act and the Exchange Act, as such Regulation is in
effect on the Issue Date.


 


“Standard &
Poor’s” means Standard & Poor’s Ratings Services, a division of The
McGraw-Hill Companies, Inc., or any successor to the rating agency
business thereof.


 


“Stated
Maturity” means, with respect to any installment of interest or principal on
any series of Indebtedness, the date on which such payment of interest or
principal was scheduled to be paid in the original documentation governing such
Indebtedness, and shall not include any contingent Obligations to repay, redeem
or repurchase any such interest or principal prior to the date originally
scheduled for the payment thereof.


 


“Subordinated
Obligation” means any Indebtedness of the Partnership or MarkWest Finance
(whether outstanding on the Issue Date or thereafter incurred) that is
subordinate or junior in right of payment to the Notes pursuant to a written
agreement.


 


“Subsidiary”
means, with respect to any Person:


 


(a)           any
corporation, association or other business entity (other than an entity
referred to in clause (b) below) of which more than 50% of the total
Voting Stock is at the time owned or controlled, directly or indirectly, by
such Person or one or more of the other Subsidiaries of that Person (or a
combination thereof); and


 


(b)           any
partnership (whether general or limited), limited liability company or joint
venture (i) the sole general partner or member of which is such Person or
a Subsidiary of such Person, or (ii) if there is more than a single
general partner or member, either (1) the only general partners, members,
managing general partners or managing members of which are such Person or one
or more Subsidiaries of such Person (or any combination thereof) or (2) such
Person owns or controls, directly or indirectly, a majority of the outstanding
general partner interests, member interests or other Voting Stock of such
partnership, limited liability company or joint venture, respectively.


 


“Subsidiary
Guarantors” means each of:


 


(a)           the
Operating Company, MarkWest Hydrocarbon, Inc., the General Partner,
MarkWest Blackhawk, L.L.C., MarkWest Energy Appalachia, L.L.C., MarkWest


 


24
















 


Energy
East Texas Gas Company, L.L.C., MarkWest Gas Services, L.L.C., MarkWest
Javelina Company, L.L.C., MarkWest Javelina Pipeline Company, L.L.C., MarkWest
Michigan Pipeline Company, L.L.C., MarkWest New Mexico, L.L.C., MarkWest
Pinnacle, L.L.C., MarkWest Pipeline Company, L.L.C., MarkWest PNG Utility,
L.L.C., MarkWest Power Tex, L.L.C., MarkWest Texas PNG Utility, L.L.C.,
MarkWest Oklahoma Gas Company, L.L.C., Mason Pipeline Limited Liability
Company, Matrex, L.L.C., MarkWest Liberty Gas Gathering, L.L.C., MarkWest
Marketing, L.L.C., MarkWest Gas Marketing, L.L.C., MarkWest McAlester, L.L.C.
and West Shore Processing Company, L.L.C.;


 


(b)           any
other Subsidiary of the Partnership that becomes a Subsidiary Guarantor in
accordance with the provisions of Section 5.13 and Article XI hereof;
and


 


(c)           their
respective successors and assigns.


 


in
each case until such Subsidiary Guarantor ceases to be such in accordance with
the Indenture. Notwithstanding anything in the Indenture to the contrary,
MarkWest Finance shall not be a Subsidiary Guarantor.


 


“Tax
Payment” means any payment of foreign, federal, state or local tax liabilities.


 


“TIA”
means the Trust Indenture Act of 1939 (15 U.S.C. §§77aaa-77bbbb), as in effect
on the date on which this Supplemental Indenture was executed and, to the
extent required by law, as amended.


 


“Treasury
Rate” means, at the time of computation, the yield to maturity of United States
Treasury Securities with a constant maturity (as compiled and published in the
most recent Federal Reserve Statistical Release H.15 (519) which has become
publicly available at least two Business Days prior to the redemption date or,
if such Statistical Release is no longer published, any publicly available
source of similar market data) most nearly equal to the period from the
redemption date to November 1, 2015; provided, however, that if such
period is not equal to the constant maturity of a United States Treasury
Security for which a weekly average yield is given, the Treasury Rate shall be
obtained by linear interpolation (calculated to the nearest one-twelfth of a
year) from the weekly average yields of United States Treasury Securities for
which such yields are given, except that if the period from the redemption date
to November 1, 2015 is less than one year, the weekly average yield on
actually traded United States Treasury Securities adjusted to a constant
maturity of one year shall be used. The Issuers will (a) calculate the
Treasury Rate on the third Business Day preceding the redemption date and (b) prior
to such redemption date file with the Trustee an Officers’ Certificate setting
forth the Make Whole Amount and the Treasury Rate and showing the calculation
of each in reasonable detail.  Any weekly
average yields calculated by interpolation shall be rounded to the nearest
1/100th of 1%, with any figure of 1/200th of 1% or above being rounded upward.


 


“Trustee”
initially means Wells Fargo Bank, National Association and any other Person or
Persons appointed as such from time to time pursuant to the Indenture, and,
subject to the provisions of Article VIII, includes its or their
successors and assigns.


 


25

















 


“U.S.
Government Obligations” means securities that are (1) direct Obligations
of the United States of America for the payment of which its full faith and
credit is pledged; (2) Obligations of a Person controlled or supervised by
and acting as an agency or instrumentality of the United States of America the
payment of which is unconditionally guaranteed as a full faith and credit
obligation by the United States of America, which, in either case under clauses
(1) or (2) above, are not callable or redeemable at the option of the
issuers thereof; or (3) depository receipts issued by a bank or trust company
as custodian with respect to any such U.S. Government Obligations or a specific
payment of interest on or principal of any such U.S. Government Obligation held
by such custodian for the account of the holder of a depository receipt,
provided that (except as required by law) such custodian is not authorized to
make any deduction from the amount payable to the holder of such depository
receipt from any amount received by the custodian in respect of the U.S.
Government Obligation evidenced by such depository receipt.


 


“Unrestricted
Subsidiary” means MarkWest Liberty Midstream & Resources, L.L.C., a
Delaware limited liability company, and any Subsidiary of the Partnership
(other than MarkWest Finance or the Operating Company) that is designated by
the Board of Directors of the General Partner as an Unrestricted Subsidiary
pursuant to a Board Resolution, but only to the extent that such Subsidiary: (1) has
no Indebtedness other than Non-Recourse Debt owing to any Person other than the
Partnership or any of its Restricted Subsidiaries, except to the extent
permitted by subclause (b)(ii) of the definition of “Permitted Business
Investments”; (2) is not a party to any agreement, contract, arrangement
or understanding with the Partnership or any Restricted Subsidiary of the
Partnership unless the terms of any such agreement, contract, arrangement or
understanding are no less favorable to the Partnership or such Restricted
Subsidiary than those that might be obtained at the time from Persons who are
not Affiliates of the Partnership; (3) is a Person with respect to which
neither the Partnership nor any of its Restricted Subsidiaries has any direct
or indirect obligation (a) to subscribe for additional Equity Interests or
(b) to maintain or preserve such Person’s financial condition or to cause
such Person to achieve any specified levels of operating results; and (4) has
not guaranteed or otherwise directly or indirectly provided credit support for
any Indebtedness of the Partnership or any of its Restricted Subsidiaries.  All Subsidiaries of an Unrestricted
Subsidiary shall be also Unrestricted Subsidiaries.  Notwithstanding anything in the Indenture to
the contrary, neither MarkWest Finance nor the Operating Company shall be
designated as an Unrestricted Subsidiary.


 


Any
designation of a Subsidiary of the Partnership as an Unrestricted Subsidiary
shall be evidenced to the Trustee by filing with the Trustee a Board Resolution
of the General Partner giving effect to such designation and an Officers’
Certificate certifying that such designation complied with the preceding
conditions and was permitted by Section 5.08 hereof. If, at any time, any
Unrestricted Subsidiary would fail to meet the preceding requirements as an
Unrestricted Subsidiary, it shall thereafter cease to be an Unrestricted
Subsidiary for purposes of the Indenture and any Indebtedness of such
Subsidiary shall be deemed to be incurred by a Restricted Subsidiary of the
Partnership as of such date and, if such Indebtedness is not permitted to be
incurred as of such date under Section 5.09 hereof, the Partnership shall
be in default of such covenant.


 


26

















 


“Voting
Stock” of any Person as of any date means the Equity Interests of such Person
pursuant to which the holders thereof have the general voting power under
ordinary circumstances to elect at least a majority of the board of directors,
managers, general partners or trustees of such Person (regardless of whether,
at the time, Equity Interests of any other class or classes shall have, or
might have, voting power by reason of the occurrence of any contingency) or,
with respect to a partnership (whether general or limited), any general partner
interest in such partnership.


 


“Weighted
Average Life to Maturity” means, when applied to any Indebtedness at any date,
the number of years obtained by dividing: (1) the sum of the products
obtained by multiplying (a) the amount of each then remaining installment,
sinking fund, serial maturity or other required payments of principal,
including payment at final maturity, in respect thereof, by (b) the number
of years (calculated to the nearest one-twelfth) that will elapse between such
date and the making of such payment; by (2) the then outstanding principal
amount of such Indebtedness.


 


Section 2.02           Other Definitions.


 


	
  Term

  	
   

  	
  Defined in Section

  
	
  “Affiliate
  Transaction”

  	
   

  	
  5.12

  
	
  “Additional
  Notes”

  	
   

  	
  Recitals

  
	
  “Asset
  Sale Offer”

  	
   

  	
  4.09

  
	
  “Base
  Indenture”

  	
   

  	
  Preamble

  
	
  “Calculation
  Date”

  	
   

  	
  2.01
  (definition of Fixed Charge Coverage Ratio)

  
	
  “Change
  of Control Offer”

  	
   

  	
  5.06(a)

  
	
  “Change
  of Control Payment”

  	
   

  	
  5.06(a)

  
	
  “Change
  of Control Payment Date”

  	
   

  	
  5.06(b)

  
	
  “Covenant
  Defeasance”

  	
   

  	
  9.03

  
	
  “Discharge”

  	
   

  	
  12.01

  
	
  “DTC”

  	
   

  	
  3.06

  
	
  “Event
  of Default”

  	
   

  	
  7.01

  
	
  “Excess
  Proceeds”

  	
   

  	
  5.07(c)

  
	
  “Guarantee”

  	
   

  	
  14.01

  
	
  “Incremental
  Funds”

  	
   

  	
  5.08

  
	
  “incur”

  	
   

  	
  5.09

  
	
  “Indenture”

  	
   

  	
  Preamble

  
	
  “Initial
  Notes”

  	
   

  	
  Recitals

  
	
  “Issuers”

  	
   

  	
  Preamble

  
	
  “Legal
  Defeasance”

  	
   

  	
  9.02

  
	
  “MarkWest
  Finance”

  	
   

  	
  Preamble

  
	
  “Notes”

  	
   

  	
  Recitals

  
	
  “Offer
  Amount”

  	
   

  	
  4.09

  
	
  “Offer
  Period”

  	
   

  	
  4.09

  
	
  “Paying
  Agent”

  	
   

  	
  3.06

  



 


27

















 


	
  “Payment
  Default”

  	
   

  	
  7.01

  
	
  “Permitted
  Debt”

  	
   

  	
  5.09

  
	
  “Purchase
  Date”

  	
   

  	
  4.09

  
	
  “Register”

  	
   

  	
  3.06

  
	
  “Registrar”

  	
   

  	
  3.06

  
	
  “Regular
  Record Date”

  	
   

  	
  3.03

  
	
  “Restricted
  Payments”

  	
   

  	
  5.08

  



 


Section 2.03           Incorporation by Reference
of Trust Indenture Act.


 


Whenever
the Indenture refers to a provision of the TIA, the provision is incorporated
by reference in and made a part of the Indenture.


 


The
following TIA term used in this Supplemental Indenture has the following
meaning:


 


“obligor” on the Notes means the Partnership, MarkWest Finance or any
Subsidiary Guarantor and any successor obligor upon the Notes.


 


All
other terms used in this Supplemental Indenture that are defined by the TIA,
defined by TIA reference to another statute or defined by SEC rule under
the TIA have the meanings so assigned to them.


 


Section 2.04           Rules of Construction.


 


Unless
the context otherwise requires:


 


(a)           a
term has the meaning assigned to it;


 


(b)           an
accounting term not otherwise defined has the meaning assigned to it in
accordance with GAAP;


 


(c)           “or”
is not exclusive;


 


(d)           words
in the singular include the plural, and in the plural include the singular;


 


(e)           provisions
apply to successive events and transactions;


 


(f)            references
to sections of or rules under the Securities Act or the Exchange Act shall
be deemed to include substitute, replacement of successor sections or rules adopted
by the SEC from time to time;


 


(g)           unless
the context otherwise requires, any reference to an “Article” or a “Section”
refers to an Article or a Section, as the case may be, of this
Supplemental Indenture; and


 


28

















 


(h)           the
words “herein”, “hereof” and “hereunder” and other words of similar import
refer to this Supplemental Indenture as a whole and not to any particular
Article, Section or other subdivision.


 


ARTICLE III

THE NOTES


 


Section 3.01           Forms Generally.


 


The
Notes and the Trustee’s certificate of authentication shall be in substantially
the form set forth in Exhibit A hereto, and the notations of
Guarantee shall be in substantially the form set forth in Exhibit B
hereto.  The Notes may have such
appropriate insertions, omissions, substitutions and other variations as are
required or permitted by the Indenture, and may have such letters, numbers or
other marks of identification and such legends or endorsements placed thereon
as may be required to comply with the rules of any securities exchange or
Depositary therefor or as may, consistently herewith, be determined by the
officers executing such Notes as evidenced by their execution thereof.


 


The
terms and provisions contained in the Notes (including the notations of
Guarantees) shall constitute, and are hereby expressly made, a part of the
Indenture, and the Issuers, the Subsidiary Guarantors and the Trustee, by their
execution and delivery of the Indenture, expressly agree to such terms and
provisions and to be bound thereby. 
However, to the extent any provision of any Note conflicts with the
express provisions of the Indenture, the provisions of the Indenture shall
govern and be controlling.


 


The
Certificated Notes shall be printed, lithographed or engraved on steel engraved
borders or may be produced in any other manner, all as determined by the
Officers executing such Notes, as evidenced by their execution of such Notes.


 


The
Initial Notes shall be issued initially in the form of a Global Note, which
shall be deposited with the Trustee, as Note Custodian. The aggregate principal
amount of any Global Note may from time to time be increased or decreased by
adjustments made on the schedule attached to such Global Note or on other
records of the Trustee, acting as Note Custodian.


 


Section 3.02           Form of Legend for
Global Notes.


 


Every
Global Note authenticated and delivered under the Indenture shall bear the
Global Note Legend in substantially the following form:


 


THIS
NOTE IS A GLOBAL NOTE WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED
TO AND IS REGISTERED IN THE NAME OF A DEPOSITARY OR A NOMINEE THEREOF. THIS
NOTE MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR A NOTE REGISTERED,
AND NO TRANSFER OF THIS NOTE IN WHOLE OR IN PART MAY BE REGISTERED, IN
THE NAME OF ANY PERSON OTHER THAN SUCH DEPOSITARY OR A NOMINEE THEREOF, EXCEPT
IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE.


 


29

















 


UNLESS
THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY
TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), NEW YORK, NEW YORK, TO THE
ISSUERS OR THEIR AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND
ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH
OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY
PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED
BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE
HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE
REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.


 


Section 3.03           Title and Terms.


 


The
Notes shall be titled the “63⁄4% Senior Notes due 2020.” The Trustee shall
authenticate the Notes to be authenticated and delivered under this
Supplemental Indenture on the Issue Date in an aggregate amount equal to
$500,000,000, upon delivery of an Issuer Order.


 


The
Notes will mature on November 1, 2020. Interest on the Notes will accrue
at the rate of 6.75% per annum and will be payable semiannually in cash on each
Interest Payment Date to the Persons who are registered Holders of Notes at the
close of business on the April 15 and October 15 (the “Regular Record
Date”) immediately preceding the applicable Interest Payment Date. Interest on
the Notes will accrue from the most recent date to which interest has been paid
or, if no interest has been paid, from and including the date of issuance to
but excluding the actual Interest Payment Date. 
If an Interest Payment Date falls on a day that is not a Business Day,
the interest payment to be made on such Interest Payment Date will be made on
the next succeeding Business Day with the same force and effect as if made on
such Interest Payment Date, and no additional interest will accrue as a result
of such delayed payment.


 


The
Notes shall be redeemable as provided in Article IV and subject to
Defeasance and Covenant Defeasance as provided in Article IX. The Notes
shall have such other terms as are indicated in Exhibit A.


 


Section 3.04           Denominations.


 


The
Notes shall be issuable only in fully registered form without coupons and only
in denominations of $2,000 and any integral multiple of $1,000 in excess
thereof.


 


Section 3.05           Execution and
Authentication.


 


One
Officer of the Partnership and one Officer of MarkWest Finance shall sign the
Notes for the Partnership and MarkWest Finance, respectively, by manual or
facsimile signature. If an Officer whose signature is on a Note no longer holds
that office at the time a Note is authenticated, the Note shall nevertheless be
valid.


 


30

















 


A
Note shall not be valid until authenticated by the manual signature of the
Trustee.  Such signature shall be
conclusive evidence that the Note has been authenticated under the Indenture.


 


The
aggregate principal amount of Notes which may be authenticated and delivered
under the Indenture is unlimited.  The
Issuers may, subject to Section 5.09 and applicable law, issue Additional
Notes under the Indenture.  The Initial
Notes and any Additional Notes subsequently issued shall be treated as a single
class for all purposes under the Indenture, including waivers, amendments,
redemptions and offers to purchase.


 


At
any time and from time to time after the execution of this Supplemental
Indenture, the Trustee shall, upon receipt of an Issuer Order, authenticate
Notes for original issue in an aggregate principal amount specified in such
Issuer Order.  The Issuer Order shall
specify the amount of Notes to be authenticated and the date on which the Notes
are to be authenticated.  The Trustee may
appoint an authenticating agent acceptable to the Issuers to authenticate
Notes.  An authenticating agent may
authenticate Notes whenever the Trustee may do so.  Each reference in the Indenture to
authentication by the Trustee includes authentication by such agent.  An authenticating agent has the same rights
as an Agent to deal with Holders or an Affiliate of either of the Issuers.


 


Each
Note shall be dated the date of its authentication.


 


No
Note shall be entitled to any benefit under the Indenture or be valid or
obligatory for any purpose unless there appears on such Note a certificate of
authentication substantially in the form provided for in Exhibit A,
signed manually in the name of the Trustee by an authorized signatory, and such
certificate upon any Note shall be conclusive evidence, and the only evidence,
that such Note has been duly authenticated and delivered hereunder.
Notwithstanding the foregoing, if any Note shall have been authenticated and
delivered hereunder but never issued and sold by the Issuers, and the Issuers
shall deliver such Note to the Trustee for cancellation as provided in
Section 3.15, for all purposes of the Indenture such Note shall be deemed
never to have been authenticated and delivered hereunder and shall never be
entitled to the benefits of the Indenture.


 


Section 3.06           Registration, Registration
of Transfer and Exchange.


 


The
Issuers and the Subsidiary Guarantors shall maintain in the continental United
States a registrar with an office or agency where Notes may be presented for
registration of transfer or for exchange (“Registrar”) and a paying agent with
an office or agency where Notes may be presented for payment (“Paying Agent”).  The Registrar shall keep a register (the “Register”)
of the Notes and of their transfer and exchange.  The Issuers may appoint one or more
co-registrars and one or more additional paying agents. The term “Registrar”
includes any co-registrar and the term “Paying Agent” includes any additional
paying agent.  The Issuers may change any
Paying Agent or Registrar without prior notice to any Holder.  The Issuers shall notify the Trustee in
writing of the name and address of any Agent not a party to the Indenture.  If the Issuers fail to


 


31

















 


appoint
or maintain another entity as Registrar or Paying Agent, the Trustee shall act
as such.  The Issuers or any of their
Subsidiaries may act as Paying Agent or Registrar.


 


The
Issuers initially appoint The Depository Trust Company (“DTC”) to act as
Depositary with respect to the Global Notes.


 


The
Issuers initially appoint the Trustee to act as the Registrar and Paying Agent
and to act as Note Custodian with respect to the Global Notes at the Corporate
Trust Office.


 


Upon
surrender for registration of transfer of any Note at the office of the
Registrar, the Issuers shall execute and the Trustee shall authenticate and
deliver, in the name of the designated transferee or transferees, one or more
new Notes, of any authorized denominations and of like tenor and aggregate
principal amount.


 


All
Notes issued upon any registration of transfer or exchange of Notes shall be
the valid obligations of the Issuers evidencing the same debt, and entitled to
the same benefits under the Indenture, as the Notes surrendered upon such
registration of transfer or exchange.


 


Every
Note presented or surrendered for registration of transfer or for exchange
shall (if so required by the Issuers or the Trustee) be duly endorsed, or be
accompanied by a written instrument of transfer in form satisfactory to the
Issuers and the Registrar duly executed, by the Holder thereof or its attorney
duly authorized in writing.


 


No
service charge shall be made for any registration of transfer or exchange of
Notes, but the Issuers may require payment of a sum sufficient to cover any
transfer tax or other governmental taxes and fees that may be imposed by law or
the Indenture in connection with any registration of transfer or exchange of
Notes.


 


If
the Notes are to be redeemed in part, the Issuers shall not be required
(A) to register the transfer of or exchange any Notes during a period of
15 days before a selection of Notes for redemption under
Section 4.02, or (B) to register the transfer of or exchange any Note
so selected for redemption in whole or in part, except the unredeemed portion
of any Note being redeemed in part. Further, the Issuers shall not be
required to register the transfer of or exchange any Notes between a
record date and the next succeeding Interest Payment Date.


 


The
provisions of clauses (a) through (d) below shall apply only to
Global Notes:


 


(a)           Each
Global Note authenticated under the Indenture shall be registered in the name
of the Depositary designated for such Global Note or a nominee thereof and
delivered to such Depositary or a nominee thereof or custodian therefor, and
each such Global Note shall constitute a single Note for all purposes of the
Indenture.


 


(b)           Notwithstanding
any other provision in the Indenture, no Global Note may be exchanged in whole
or in part for Notes registered, and no transfer of a Global Note in whole or
in part may be registered, in the name of any Person other than the Depositary
for such Global Note or a nominee thereof, unless (A) such Depositary
(i) has notified the Issuers that it is no


 


32

















 


longer
willing or able to discharge its responsibilities properly as Depositary for
such Global Note or (ii) has ceased to be a clearing agency registered
under the Exchange Act, and in either case the Issuers have not appointed a
qualified successor within 90 days, (B) an Event of Default has
occurred and is continuing and the Depositary has notified the Issuers and the
Trustee of its desire to exchange such Global Note for Certificated Notes or
(C) subject to the Depositary’s rules, the Issuers, at their option, have
elected to terminate the book-entry system through the Depositary.


 


(c)           Subject
to clause (b) above, any exchange of a Global Note for other Notes may be
made in whole or in part, and all Notes issued in exchange for a Global Note or
any portion thereof shall be registered in such names as the Depositary for
such Global Note shall direct.


 


(d)           Every
Note authenticated and delivered upon registration of transfer of, or in
exchange for or in lieu of, a Global Note or any portion thereof, whether
pursuant to this Section or otherwise, shall be authenticated and
delivered in the form of, and shall be, a Global Note, unless such Note is
registered in the name of a Person other than the Depositary for such Global
Note or a nominee thereof.


 


Section 3.07           Paying Agent to Hold Money
in Trust.


 


The
Issuers shall require each Paying Agent other than the Trustee to agree in
writing that the Paying Agent will hold in trust for the benefit of Holders or
the Trustee all money held by the Paying Agent for the payment of principal,
premium, if any, or interest, on the Notes, and will notify the Trustee of any
default by the Partnership, MarkWest Finance or the Subsidiary Guarantors in
making any such payment.  While any such
default continues, the Trustee may require a Paying Agent to pay all money held
by it to the Trustee.  The Issuers at any
time may require a Paying Agent to pay all money held by it to the
Trustee.  Upon payment over to the
Trustee, the Paying Agent (if other than an Issuer or a Subsidiary Guarantor)
shall have no further liability for the money. 
If an Issuer or a Subsidiary Guarantor acts as Paying Agent, it shall
segregate and hold in a separate trust fund for the benefit of the Holders all
money held by it as Paying Agent.  Upon
any bankruptcy or reorganization proceedings relating to the Partnership or
MarkWest Finance, the Trustee shall serve as Paying Agent for the Notes.


 


Section 3.08           Holder Lists.


 


The
Trustee shall preserve in as current a form as is reasonably practicable the
most recent list available to it of the names and addresses of all Holders and
shall otherwise comply with TIA Section 312(a).  If the Trustee is not the Registrar, the
Issuers shall furnish to the Trustee at least seven Business Days before each
Interest Payment Date and at such other times as the Trustee may request in
writing, a list in such form and as of such date as the Trustee may reasonably
require of the names and addresses of the Holders of Notes and the Issuers
shall otherwise comply with TIA Section 312(a).


 


33

















 


Section 3.09           Mutilated, Destroyed, Lost
and Stolen Notes.


 


If
any mutilated Note is surrendered to the Trustee or either of the Issuers and
the Trustee receives evidence to its satisfaction of the destruction, loss or
theft of any Note, the Issuers shall issue and the Trustee, upon receipt of an
Issuer Order, shall authenticate a replacement Note (accompanied by a notation
of the Guarantees duly endorsed by the Subsidiary Guarantors) if the Trustee’s
requirements are met.  An indemnity bond
must be supplied by the Holder that is sufficient in the judgment of the
Trustee and the Issuers to protect the Issuers, the Subsidiary Guarantors, the
Trustee, any Agent and any authenticating agent from any loss that any of them
may suffer if a Note is replaced.  The
Issuers may charge for their expenses in replacing a Note.


 


Every
replacement Note is an additional obligation of the Issuers and the Subsidiary
Guarantors and shall be entitled to all of the benefits of the Indenture
equally and proportionately with all other Notes duly issued hereunder.  The provisions of this Section 3.09 are
exclusive and shall preclude (to the extent lawful) all other rights and
remedies with respect to the replacement of mutilated, destroyed, lost or
stolen Notes.


 


Section 3.10           Outstanding Notes.


 


The
Notes outstanding at any time are all the Notes authenticated by the Trustee
except for those canceled by it, those delivered to it for cancellation, those
reductions in the interests in a Global Note effected by the Trustee in
accordance with the provisions hereof, and those described in this Section as
not outstanding.  Except as set forth in Section 3.11
hereof, a Note does not cease to be outstanding because an Issuer or an
Affiliate of an Issuer holds the Note.


 


If
a Note is replaced pursuant to Section 3.09 hereof, it ceases to be
outstanding unless the Trustee receives proof satisfactory to it that the
replaced Note is held by a protected purchaser.


 


If
the principal amount of any Note is considered paid under Section 5.01
hereof, it ceases to be outstanding and interest on it ceases to accrue.


 


If
the Paying Agent (other than an Issuer or a Subsidiary or an Affiliate of an
Issuer) holds, on a redemption date or other maturity date, money sufficient to
pay Notes payable on that date, then on and after that date such Notes shall be
deemed to be no longer outstanding and shall cease to accrue interest.


 


Section 3.11           Treasury Notes.


 


In
determining whether the Holders of the required principal amount of Notes have
concurred in any direction, waiver or consent, Notes owned by an Issuer, by any
Subsidiary Guarantor or by any Person directly or indirectly controlling or
controlled by or under direct or indirect common control with the Partnership
or any Subsidiary Guarantor, shall be considered as though not outstanding,
except that for the purposes of determining whether the Trustee shall be
protected in relying on any such direction, waiver or consent, only Notes that
a Responsible Officer of the Trustee actually knows are so owned shall be so
disregarded.


 


34

















 


Section 3.12           Payment of Interest;
Interest Rights Preserved.


 


If
a Holder has given wire transfer instructions to the Issuers, the Issuers will
make all payments of principal of, premium, if any, and interest on the Notes
in accordance with those instructions. 
All other payments in respect of the Notes shall be made at the office
or agency of the Paying Agent in Dallas, Texas; provided that the Issuers may,
at their option, pay interest on the Notes by check mailed to the Holders at
their registered address as it appears in the Register.


 


The
Company shall pay principal of, premium, if any, and interest on the Global
Notes registered in the name of or held by DTC or its nominee in immediately
available funds to DTC or its nominee, as the case may be, as the registered
Holder of such Global Notes.


 


Interest
on any Note which is payable, and is punctually paid or duly provided for, on
any Interest Payment Date shall be paid to the Person in whose name that Note
is registered at the close of business on the Regular Record Date for such
interest.


 


If
any of the Partnership, MarkWest Finance or any Subsidiary Guarantor defaults
in a payment of interest on the Notes, it or they (to the extent of their
obligations under the Guarantees) shall pay the defaulted interest in any
lawful manner plus, to the extent lawful, interest payable on the defaulted
interest, to the Persons who are Holders on a subsequent special record date,
in each case at the rate provided in the Notes and in Section 3.03
hereof.  The Issuers shall notify the
Trustee in writing of the amount of defaulted interest proposed to be paid on
each Note, the special record date and the date of the proposed payment.  The Issuers shall fix or cause to be fixed
each such special record date and payment date, provided that no such special
record date shall be less than 10 days prior to the related payment date for
such defaulted interest.  At least 15
days before the special record date, the Issuers (or, upon the written request
of the Issuers, the Trustee in the name and at the expense of the Issuers)
shall mail or cause to be mailed to Holders a notice that states the special
record date, the related payment date and the amount of such interest to be
paid.


 


Subject
to the foregoing provisions of this Section, each Note delivered under the
Indenture upon registration of transfer of or in exchange for or in lieu of any
other Note shall carry the rights to interest accrued and unpaid, and to
accrue, which were carried by such other Note.


 


Section 3.13           Persons
Deemed Owners.


 


Prior
to due presentment of a Note for registration of transfer, the Issuers, the
Subsidiary Guarantors, the Trustee and any agent of the Issuers or the Trustee
may treat the Person in whose name such Note is registered as the owner of such
Note for the purpose of receiving payment of principal of, and any premium and
(subject to Section 407) any interest on, such Note and for all other
purposes whatsoever, whether or not such Note be overdue, and none of the
Issuers, the Subsidiary Guarantors, the Trustee nor any of their respective
agents shall be affected by notice to the contrary.


 


35

















 


None
of the Issuers, the Subsidiary Guarantors, the Trustee, nor any of their
respective agents will have any responsibility or liability for any aspect of
the records relating to, or payments made on account of, Beneficial Ownership
interests of a Note or for maintaining, supervising or reviewing any records
relating to such Beneficial Ownership interests.


 


Section 3.14           Temporary Notes.


 


Until
Certificated Notes are ready for delivery, the Issuers may prepare and the
Trustee, upon receipt of an Issuer Order, shall authenticate temporary Notes
(accompanied by a notation of the Guarantees duly endorsed by the Subsidiary
Guarantors).  Temporary Notes shall be
substantially in the form of Certificated Notes but may have variations that
the Issuers consider appropriate for temporary Notes and as shall be reasonably
acceptable to the Trustee.  Without
unreasonable delay, the Issuers shall prepare and the Trustee, upon receipt of
an Issuer Order, shall authenticate Certificated Notes (accompanied by a
notation of the Guarantees duly endorsed by the Subsidiary Guarantors) in
exchange for temporary Notes.


 


Holders
of temporary Notes shall be entitled to all of the benefits of the Indenture.


 


Section 3.15           Cancellation.


 


Either
of the Issuers at any time may deliver Notes to the Trustee for
cancellation.  The Registrar and Paying
Agent shall forward to the Trustee any Notes surrendered to them for
registration of transfer, exchange or payment. 
The Trustee and no one else shall cancel all Notes surrendered for
registration of transfer, exchange, payment, replacement or cancellation and
shall treat such canceled Notes in accordance with its documents retention
policies.  The Issuers may not issue new
Notes to replace Notes that have been paid or that have been delivered to the
Trustee for cancellation.


 


Section 3.16           Computation of Interest.


 


Interest
on the Notes shall be computed on the basis of a 360-day year of twelve 30-day
months.


 


Section 3.17           Global Securities.


 


Neither
the Trustee nor any Agent shall have any responsibility for any actions taken
or not taken by the Depositary.


 


Section 3.18           CUSIP Numbers.


 


The
Issuers in issuing the Notes may use “CUSIP” numbers (if then generally in
use), and, if they do so, the Trustee shall use “CUSIP” numbers in notices of
redemption as a convenience to Holders; provided that any such notice may state
that no representation is made as to the correctness of such numbers either as
printed on the Notes or as contained in any notice of a redemption and that
reliance may be placed only on the other identification numbers printed


 


36
















 


on
the Notes, and any such redemption shall not be affected by any defect in or
omission of such numbers.  The Issuers
will promptly notify the Trustee of any change in the “CUSIP” numbers.


 


ARTICLE IV

REDEMPTION AND PREPAYMENT OF NOTES


 


Section 4.01           Notices to Trustee.


 


If
an Issuer elects to redeem Notes pursuant to the optional redemption provisions
of Section 4.07 hereof, it shall furnish to the Trustee, at least ten
Business Days (unless a shorter period is acceptable to the Trustee) before the
date of giving notice of the redemption pursuant to Section 4.03, an
Officers’ Certificate setting forth (i) the clause of this Supplemental
Indenture pursuant to which the redemption shall occur, (ii) the
redemption date, (iii) the principal amount of Notes to be redeemed, (iv) the
redemption price and (v) whether it requests the Trustee to give notice of
such redemption.  Any such notice may be
cancelled at any time prior to the mailing of notice of such redemption to any
Holder and shall thereby be void and of no effect.


 


Section 4.02           Selection of Notes to Be
Redeemed.


 


If
less than all of the Notes are to be redeemed at any time, the Trustee will
select Notes for redemption as follows:


 


(a)           if
the Notes are listed for trading on a national securities exchange, in
compliance with the requirements of the principal national securities exchange
on which the Notes are so listed; or


 


(b)           if
the Notes are not so listed or there are no such requirements, on a pro rata
basis (or, in the case of Notes in global form, the Trustee will select Notes
for redemption based on DTC’s method that most nearly approximates a pro rata
selection), by lot or by such method as the Trustee shall deem fair and
appropriate.


 


No
Notes of $2,000 or less shall be redeemed in part.  Notices of redemption shall be mailed by
first class mail at least 30 but not more than 60 days before the redemption
date to each Holder of Notes to be redeemed at its registered address.  Notices of redemption may not be conditional,
except that any redemption described under Section 4.07(c) may at the
Issuers’ discretion, be conditioned upon completion of the related Equity
Offering.


 


If
any Note is to be redeemed in part only, the notice of redemption that relates
to that Note shall state the portion of the principal amount thereof to be
redeemed.  A new Note in principal amount
equal to the unredeemed portion of the original Note will be issued in the name
of the Holder thereof upon cancellation of the original Note.  Except as provided in the immediately preceding
paragraph, Notes called for redemption become due on the date fixed for
redemption.  On and after the redemption
date, interest ceases to accrue on Notes or portions of them called for
redemption unless the Issuers default in making such redemption payment.


 


37

















 


Section 4.03           Notice of Redemption.


 


At
least 30 days but not more than 60 days before a redemption date, the Issuers
shall mail or cause to be mailed, by first class mail, a notice of redemption
to each Holder whose Notes are to be redeemed at its registered address, except
that redemption notices may be mailed more than 60 days prior to a redemption
date if the notice is issued in connection with a Legal Defeasance, Covenant
Defeasance or Discharge.


 


The
notice shall identify the Notes to be redeemed (including CUSIP numbers) and
shall state:


 


(a)           the
redemption date;


 


(b)           the
redemption price (if then determined and otherwise the basis for its
determination);


 


(c)           if
any Note is being redeemed in part, the portion of the principal amount of such
Note to be redeemed and that, after the redemption date upon surrender of such
Note, a new Note or Notes in principal amount equal to the unredeemed portion
shall be issued upon cancellation of the original Note;


 


(d)           the
name and address of the Paying Agent;


 


(e)           that
Notes called for redemption (other than a Global Note) must be surrendered to
the Paying Agent to collect the redemption price;


 


(f)            that,
unless the Issuers default in making such redemption payment, interest on Notes
called for redemption ceases to accrue on and after the redemption date;


 


(g)           the
paragraph of the Notes and/or Section of this Supplemental Indenture
pursuant to which the Notes called for redemption are being redeemed; and


 


(h)           that
no representation is made as to the correctness or accuracy of the CUSIP
number, if any, listed in such notice or printed on the Notes.


 


If
any of the Notes to be redeemed is in the form of a Global Note, then the
Issuers shall modify such notice to the extent necessary to accord with the
procedures of the Depositary applicable to redemption.


 


At
the Issuers’ request, the Trustee shall give the notice of redemption in the
Issuers’ names and at their expense; provided, however, that the Issuers shall
have delivered to the Trustee, as provided in Section 4.01, an Officers’
Certificate requesting that the Trustee give such notice and setting forth the
information to be stated in such notice as provided in the preceding paragraph.


 


38

















 


Section 4.04           Effect of Notice of
Redemption.


 


Once
notice of redemption is mailed in accordance with Section 4.03 hereof,
Notes called for redemption become irrevocably due and payable on the
redemption date at the redemption price. 
A notice of redemption may not be conditional, except as otherwise
permitted in the Indenture.


 


Section 4.05           Deposit of Redemption
Price.


 


Not
later than 11:00 a.m., New York City time, on the redemption date, the
Issuers shall deposit with the Trustee or with the Paying Agent (or, if the
Partnership or a Subsidiary thereof is acting as its own Paying Agent,
segregate and hold in trust as provided in Section 3.07 hereof) money
sufficient to pay the redemption price of, and accrued and unpaid interest on,
all Notes to be redeemed on that date. 
The Trustee or the Paying Agent shall promptly return to the Issuers any
money deposited with the Trustee or the Paying Agent by the Issuers in excess
of the amounts necessary to pay the redemption price of, and accrued and unpaid
interest on, all Notes to be redeemed.


 


If
the Issuers comply with the provisions of the preceding paragraph, on and after
the redemption date, interest shall cease to accrue on the Notes or the
portions of Notes called for redemption. 
If a Note is redeemed on or after an interest record date but on or
prior to the related Interest Payment Date, then any accrued and unpaid
interest shall be paid to the Person in whose name such Note was registered at
the close of business on such record date. 
If any Note called for redemption shall not be so paid upon surrender
for redemption because of the failure of the Issuers to comply with the
preceding paragraph, interest shall be paid on the unpaid principal, from the
redemption date until such principal is paid, and to the extent lawful on any
interest not paid on such unpaid principal, in each case at the rate provided
in the Notes and in Section 3.03 hereof.


 


Section 4.06           Notes Redeemed in Part.


 


Upon
surrender of a Note that is redeemed in part, the Issuers shall issue and, upon
receipt of an Issuer Order, the Trustee shall authenticate for the Holder at
the expense of the Issuers a new Note (accompanied by a notation of the
Guarantees duly endorsed by the Subsidiary Guarantors) equal in principal
amount to the unredeemed portion of the Note surrendered.


 


Section 4.07           Optional Redemption.


 


(a)           Except
as set forth in clauses (b) and (c) of this Section 4.07 and in Section 5.06(h),
the Issuers shall not have the option to redeem the Notes prior to November 1,
2015.  On or after November 1, 2015,
the Issuers shall have the option to redeem all or, from time to time, a part
of the Notes, at the redemption prices (expressed as percentages of principal
amount) set forth below, plus accrued and unpaid interest on the Notes, if any,
to the applicable redemption date (subject to the rights of Holders of record
on the relevant record date to receive


 


39

















 


interest
due on an Interest Payment Date that is on or prior to the redemption date), if
redeemed during the twelve-month period beginning on November 1 of the
years indicated below:


 


	
  Year

  	
   

  	
  Percentage

  	
   

  
	
  2015

  	
   

  	
  103.375

  	
  %

  
	
  2016

  	
   

  	
  102.250

  	
  %

  
	
  2017

  	
   

  	
  101.125

  	
  %

  
	
  2018
  and thereafter

  	
   

  	
  100.000

  	
  %

  



 


(b)           Before
November 1, 2015, the Issuers may redeem all or, from time to time, a part
of the Notes, at a redemption price equal to:


 


(i)            100% of the aggregate principal amount of the Notes to be
redeemed, plus accrued and unpaid interest, if any, to the applicable
redemption date (subject to the right of Holders of record on the relevant
record date to receive interest due on an Interest Payment Date that is on or
prior to the redemption date), plus


 


(ii)           the Make Whole Amount.


 


(c)           Before
November 1, 2013, the Issuers may on any one or more occasions redeem in
the aggregate up to 35% of the aggregate principal amount of Notes issued
hereunder, with the net cash proceeds of one or more Equity Offerings at a
redemption price equal to 106.750% of the principal amount of the Notes to be
redeemed, plus accrued and unpaid interest, if any, to the redemption date
(subject to the right of Holders of record on the relevant record date to
receive interest due on an Interest Payment Date that is on or prior to the
redemption date); provided that


 


(i)            at least 65% of the aggregate principal amount of Notes
issued hereunder remains outstanding after each such redemption; and


 


(ii)           any redemption occurs within 60 days after the closing of
such Equity Offering (without regard to any over-allotment option).


 


Any
redemption pursuant to this Section 4.07 shall be made pursuant to the
provisions of Section 4.01 through 4.06 hereof.


 


Section 4.08           Mandatory Redemption.


 


Except
for any repurchase offers required to be made pursuant to Sections 5.06 and 5.07
hereof, the Issuers shall not be required to make mandatory redemption or
sinking fund payments with respect to the Notes or to repurchase the Notes at
the option of the Holders.


 


Section 4.09           Offer to Purchase by
Application of Net Proceeds.


 


In
the event that, pursuant to Section 5.07 hereof, the Partnership shall be
required to commence a pro rata offer (an “Asset Sale Offer”) to all Holders
and all holders of other


 


40

















 


Indebtedness
that is pari passu with the Notes containing provisions similar to those set
forth in the Indenture with respect to offers to purchase or redeem with the
Net Proceeds of sales of assets to purchase Notes and such other pair passu
Indebtedness, it shall follow the procedures specified below.


 


The
Asset Sale Offer shall remain open for a period of at least 30 days following
its commencement but no longer than 60 days, except to the extent that a longer
period is required by applicable law (the “Offer Period”).  Promptly after the termination of the Offer
Period (the “Purchase Date”), the Partnership shall purchase the principal
amount of Notes required to be purchased pursuant to Section 5.07 hereof
(the “Offer Amount”) or, if less than the Offer Amount has been tendered, all
Notes tendered and not withdrawn in response to the Asset Sale Offer.  Payment for any Notes so purchased shall be
made in the same manner as interest payments are made.


 


Upon
the commencement of an Asset Sale Offer, the Partnership shall send, by first
class mail, a notice to the Trustee and each of the Holders, with a copy to the
Trustee.  The notice shall contain all
instructions and materials necessary to enable such Holders to tender Notes
pursuant to the Asset Sale Offer.  The
Asset Sale Offer shall be made to all Holders. 
The notice, which shall govern the terms of the Asset Sale Offer, shall
state:


 


(a)           that
the Asset Sale Offer is being made pursuant to this Section 4.09 and Section 5.07
hereof and the length of time the Asset Sale Offer shall remain open;


 


(b)           the
Offer Amount, the purchase price and the Purchase Date;


 


(c)           that
any Note not validly tendered or accepted for payment shall continue to accrue
interest;


 


(d)           that,
unless the Partnership defaults in making such payment, any Note accepted for
payment pursuant to the Asset Sale Offer shall cease to accrue interest after
the Purchase Date;


 


(e)           that
Holders electing to have a Note purchased pursuant to any Asset Sale Offer
shall be required to surrender the Note, with the form entitled “Option of
Holder to Elect Purchase” on the reverse of the Note completed, or transfer by
book-entry transfer, to the Partnership, a depositary, if appointed by the
Partnership, or a Paying Agent at the address specified in the notice at least
three days before the Purchase Date;


 


(f)            that
Holders shall be entitled to withdraw their election if the Partnership, the
depositary or the Paying Agent, as the case may be, receives, not later than
the expiration of the Offer Period, a telegram, facsimile transmission or letter
setting forth the name of the Holder, the principal amount of the Note the
Holder delivered for purchase and a statement that such Holder is withdrawing
his election to have such Note purchased;


 


(g)           that,
if the aggregate principal amount of Notes surrendered by Holders exceeds the
Offer Amount, the Issuers shall select the Notes to be purchased on a pro rata
basis


 


41

















 


(with
such adjustments as may be deemed appropriate by the Issuers so that only Notes
in minimum denominations of $2,000 or integral multiples of $1,000 in excess
thereof, shall be purchased); and


 


(h)           that
Holders whose Notes were purchased only in part shall be issued new Notes
(accompanied by a notation of the Guarantees duly endorsed by the Subsidiary
Guarantors) equal in principal amount to the unpurchased portion of the Notes
surrendered (or transferred by book-entry transfer).


 


On
the Purchase Date, the Partnership shall, to the extent lawful, accept for
payment, on a pro rata basis to the extent necessary, the Offer Amount of Notes
or portions thereof validly tendered and not properly withdrawn pursuant to the
Asset Sale Offer, or if less than the Offer Amount has been validly tendered
and not properly withdrawn, all Notes so tendered and not withdrawn, shall
deposit by 11:00 a.m., New York City time, with the Paying Agent or
depositary an amount equal to the purchase price in respect of all Notes or
portions thereof accepted for payment, and shall deliver to the Trustee an
Officers’ Certificate stating that such Notes or portions thereof were accepted
for payment by the Partnership in accordance with the terms of this Section 4.09.  Upon surrender and cancellation of a
Certificated Note that is purchased in part, the Issuers shall promptly issue
and the Trustee, upon receipt of an Issuer Order, shall authenticate and
deliver to the surrendering Holder of such Certificated Note a new Certificated
Note equal in principal amount to the unpurchased portion of such surrendered
Certificated Note; provided that each such new Certificated Note shall be in a
minimum principal amount of $2,000 or an integral multiple of $1,000 in excess
thereof.  Respecting a Global Note that
is purchased in part pursuant to an Asset Sale Offer, the Trustee shall make an
endorsement thereon to reduce the principal amount of such Global Note to an
amount equal to the unpurchased portion of such Global Note, as provided in Section 3.06
hereof.  The depositary or the Paying
Agent, as the case may be, shall promptly mail or deliver to each tendering
Holder an amount equal to the purchase price of the Notes tendered by such
Holder and accepted by the Partnership for purchase, and the Issuers shall
promptly issue a new Note (in each case, accompanied by a notation of the
Guarantees duly endorsed by the Subsidiary Guarantors), and the Trustee, upon
receipt of an Issuer Order, shall authenticate and mail or deliver such new
Note to such Holder, in a principal amount equal to any unpurchased portion of
the Note surrendered.  Any Note not so
accepted shall be promptly mailed or delivered by the Partnership to the Holder
thereof.  The Partnership shall publicly
announce the results of the Asset Sale Offer on or as soon as practicable after
the Purchase Date.


 


ARTICLE V

COVENANTS


 


Section 5.01           Payment of Notes.


 


The
Issuers shall pay or cause to be paid the principal of and premium, if any, and
interest on the Notes on the dates and in the manner provided in the
Notes.  Principal, premium, if any, and
interest shall be considered paid on the date due if the Paying Agent, if other
than an Issuer or any Subsidiary Guarantor thereof, holds as of 11:00 a.m.
Eastern Time on the due date


 


42

















 


money
deposited by the Issuers in immediately available funds and designated for and
sufficient to pay all principal, premium, if any, and interest then due.


 


The
Issuers shall pay interest (including post-petition interest in any proceeding
under any Bankruptcy Law) on overdue principal and premium at the then
applicable interest rate on the Notes to the extent lawful.  The Issuers shall pay interest (including
post-petition interest in any proceeding under any Bankruptcy Law) on overdue
installments of interest, without regard to any applicable grace period, at the
same rate to the extent lawful.


 


Section 5.02           Maintenance of Office or
Agency.


 


The
Issuers shall maintain in the continental United States an office or agency
(which may be an office of the Trustee or an Affiliate of the Trustee, Registrar
or co-registrar), where Notes may be surrendered or presented for payment,
where Notes may be surrendered for registration of transfer or for exchange and
where notices and demands to or upon the Issuers or the Subsidiary Guarantors
in respect of the Notes and the Indenture may be served.  The Issuers shall give prompt written notice
to the Trustee of the location, and any change in the location, of such office
or agency.  If at any time the Issuers
shall fail to maintain any such required office or agency or shall fail to
furnish the Trustee with the address thereof, such presentations, surrenders,
notices and demands may be made or served at the Corporate Trust Office of the
Trustee.


 


The
Issuers may also from time to time designate one or more other offices or
agencies where the Notes may be presented or surrendered for any or all such
purposes and may from time to time rescind such designations.  The Issuers shall give prompt written notice
to the Trustee of any such designation or rescission and of any change in
location of any such other office or agency.


 


The
Issuers hereby designate the Corporate Trust Office of the Trustee as one such
office or agency of the Issuers in accordance with Section 3.06.


 


Section 5.03           Compliance Certificate.


 


(a)           The
Issuers and the Subsidiary Guarantors shall deliver to the Trustee, within 90
days after the end of each fiscal year, an Officers’ Certificate stating that a
review of the activities of the Issuers and the Restricted Subsidiaries of the
Partnership during the preceding fiscal year has been made under the
supervision of the signing Officers with a view to determining whether the
Issuers and the Subsidiary Guarantors have kept, observed, performed and
fulfilled their respective obligations under the Indenture and the Guarantees,
respectively, and further stating, as to each such Officer signing such
certificate, that to the best of his or her knowledge each of such Issuers and
such Subsidiary Guarantors, as the case may be, has kept, observed, performed
and fulfilled each and every covenant contained in the Indenture and is not in
default in the performance or observance of any of the terms, provisions and
conditions of the Indenture (or, if a Default or Event of Default shall have
occurred and be continuing, describing all such Defaults or Events of Default
of which he or she may have knowledge and what action


 


43

















 


such
Issuer or such Subsidiary Guarantor, as the case may be, is taking or proposes
to take with respect thereto).


 


(b)           Each
of the Issuers shall, so long as any of the Notes are outstanding, deliver to
the Trustee, forthwith upon any Officer of the General Partner or MarkWest
Finance becoming aware of any Default or Event of Default, an Officers’
Certificate specifying such Default or Event of Default and what action the
Issuers are taking or propose to take with respect thereto.


 


Section 5.04           Taxes.


 


The
Issuers shall pay, and shall cause each of its Restricted Subsidiaries to pay,
prior to delinquency, all material taxes, assessments, and governmental levies
except such as are contested in good faith and by appropriate proceedings or
where the failure to effect such payment is not adverse in any material respect
to the Holders of the Notes.


 


Section 5.05           Stay, Extension and Usury
Laws.


 


Each
of the Issuers and the Subsidiary Guarantors covenants (to the extent that it
may lawfully do so) that it shall not at any time insist upon, plead, or in any
manner whatsoever claim or take the benefit or advantage of, any stay,
extension or usury law wherever enacted, now or at any time hereafter in force,
that may affect the covenants or the performance of the Indenture; and each of
the Issuers and the Subsidiary Guarantors (to the extent that it may lawfully
do so) hereby expressly waives all benefit or advantage of any such law, and
covenants that it shall not, by resort to any such law, hinder, delay or impede
the execution of any power herein granted to the Trustee, but shall suffer and
permit the execution of every such power as though no such law has been
enacted.


 


Section 5.06           Change of Control.


 


(a)           If
a Change of Control occurs, each Holder of Notes shall have the right to
require the Partnership to repurchase all or any part (equal to $2,000 or an
integral multiple of $1,000 in excess thereof) of that Holder’s Notes pursuant
to the offer described below (the “Change of Control Offer”). In the Change of
Control Offer, the Partnership shall offer a “Change of Control Payment” in
cash equal to 101% of the aggregate principal amount of Notes repurchased plus
accrued and unpaid interest thereon, if any, to the date of purchase (the “Change
of Control Payment”), subject to the rights of any Holder in whose name a Note
is registered on a record date occurring prior to the Change of Control Payment
Date to receive interest due on an Interest Payment Date that is on or prior to
such Change of Control Payment Date. Within 30 days following any Change of
Control, the Partnership shall mail a notice to each Holder describing the
transaction or transactions that constitute the Change of Control and offering
to repurchase Notes on the Change of Control Payment Date specified in such
notice, pursuant to the procedures required by the Indenture and described in
such notice. The Partnership shall comply with the requirements of Rule 14e-1
under the Exchange Act and any other securities laws and regulations thereunder
to the extent such laws and regulations are


 


44

















 


applicable
in connection with the repurchase of the Notes as a result of a Change of
Control. To the extent that the provisions of any securities laws or
regulations conflict with the provisions of this Section 5.06, the
Partnership shall comply with the applicable securities laws and regulations
and shall not be deemed to have breached their obligations under this Section 5.06
by virtue of such conflict.


 


(b)           Within
30 days following any Change of Control, the Partnership shall mail by first
class mail, a notice to each Holder, with a copy of such notice to the
Trustee.  The notice, which shall govern
the terms of the Change of Control Offer, shall state, among other things:


 


(i)            that a Change of Control has occurred and a Change of
Control Offer is being made as provided for herein, and that, although Holders
are not required to tender their Notes, all Notes that are validly tendered
shall be accepted for payment;


 


(ii)           the Change of Control Payment and the Change of Control
Payment Date, which will be no earlier than 30 days and no later than 60 days
after the date such notice is mailed (the “Change of Control Payment Date”);


 


(iii)          that any Note accepted for payment pursuant to the Change
of Control Offer (and duly paid for on the Change of Control Payment Date)
shall cease to accrue interest after the Change of Control Payment Date;


 


(iv)          that any Notes (or portions thereof) not validly tendered
shall continue to accrue interest;


 


(v)           that any Holder electing to have a Note purchased pursuant
to any Change of Control Offer shall be required to surrender the Note, with
the form entitled “Option of Holder to Elect Purchase” on the reverse of the
Note completed, or transfer by book-entry transfer, to the Partnership, a
depositary, if appointed by the Partnership, or a Paying Agent at the address
specified in the notice at least one (1) Business Day before the Change of
Control Payment Date;


 


(vi)          that Holders shall be entitled to withdraw their election
if the Partnership, the depositary or the Paying Agent, as the case may be, receives,
not later than the expiration of the Change of Control Offer, a telegram,
facsimile transmission or letter setting forth the name of the Holder, the
principal amount of the Note the Holder delivered for purchase and a statement
that such Holder is withdrawing his election to have such Note purchased; and


 


(vii)         the instructions and any other information necessary to
enable Holders to tender their Notes (or portions thereof) and have such Notes
(or portions thereof) purchased pursuant to the Change of Control Offer.


 


45

















 


(c)           On
or before the Change of Control Payment Date, the Partnership shall, to the
extent lawful, accept for payment all Notes or portions thereof properly
tendered and not withdrawn pursuant to the Change of Control Offer.  Promptly after such acceptance, on the Change
of Control Payment Date, the Partnership will:


 


(i)            deposit by 11:00 a.m., New York City time, with the
Paying Agent or depositary an amount equal to the Change of Control Payment in
respect of all Notes or portions thereof so tendered; and


 


(ii)           deliver or cause to be delivered to the Trustee for
cancellation the Notes so accepted together with an Officers’ Certificate
stating the aggregate principal amount of Notes or portions thereof being
purchased by the Partnership.


 


(d)           On
the Change of Control Payment Date, the Paying Agent shall mail to each Holder
of Notes accepted for payment the Change of Control Payment for such Notes (or,
if all the Notes are then in global form, make such payment through the
facilities of DTC), and the Issuers shall promptly issue a new Note (in each
case, accompanied by a notation of the Guarantees duly endorsed by the
Subsidiary Guarantors), and the Trustee, upon receipt of an Issuer Order, shall
authenticate and mail (or cause to be transferred by book entry) to each Holder
such new Note equal in principal amount to any unpurchased portion of the Notes
surrendered; provided that each such new Note shall be in a principal amount of
$2,000 or an integral multiple of $1,000 in excess thereof.  The Partnership shall publicly announce the
results of the Change of Control Offer on or as soon as practicable after the
Change of Control Payment Date.


 


(e)           The
provisions described in this Section 5.06 that require the Issuers to make
a Change of Control Offer following a Change of Control shall be applicable
regardless of whether or not any other provisions of the Indenture are
applicable.


 


(f)            Notwithstanding
the other provisions of this Section 5.06, the Partnership shall not be
required to make a Change of Control Offer upon a Change of Control, and a
Holder will not have the right to require that the Partnership repurchase any
Notes pursuant to a Change of Control Offer, if (1) a third party makes
the Change of Control Offer in the manner, at the times and otherwise in
compliance with the requirements set forth in the Indenture applicable to a
Change of Control Offer made by the Partnership and purchases all Notes validly
tendered and not withdrawn under such Change of Control Offer or (2) notice
of redemption has been given pursuant to the Indenture.


 


(g)           A
Change of Control Offer may be made in advance of a Change of Control, and
conditioned upon the occurrence of the Change of Control, if a definitive
agreement is in place for the Change of Control at the time of making the
Change of Control Offer.


 


(h)           In
the event that Holders of not less than 90% of the aggregate principal amount
of the outstanding Notes accept a Change of Control Offer and the Partnership
purchases all of the Notes held by such Holders, the Issuers will have the
right, upon not less than 30 nor


 


46

















 


more
than 60 days’  notice, given not more
than 30 days following the purchase pursuant to the Change of Control Offer
described above, to redeem all of the Notes that remain outstanding following
such purchase at a redemption price equal to the Change of Control Payment
plus, to the extent not included in the Change of Control Payment, accrued and
unpaid interest on the notes that remain outstanding, to the date of redemption
(subject to the right of holders of record on the relevant record date to
receive interest due on an Interest Payment Date that is on or prior to the
redemption date).


 


Section 5.07           Asset Sales.


 


The
Partnership shall not, and shall not permit any of its Restricted Subsidiaries
to, consummate an Asset Sale unless:


 


(a)           the
Partnership (or the Restricted Subsidiary, as the case may be) receives
consideration at the time of such Asset Sale at least equal to the fair market
value of the assets or Equity Interests issued or sold or otherwise disposed
of;


 


(b)           such
fair market value is determined by (a) an executive officer of the General
Partner if the value is less than $30.0 million, as evidenced by an Officers’
Certificate delivered to the Trustee or (b) the Board of Directors of the
General Partner if the value is $30.0 million or more, as evidenced by a
resolution of such Board of Directors of the General Partner; and


 


(c)           at
least 75% of the aggregate consideration received by the Partnership and its
Restricted Subsidiaries in the Asset Sale and all other Asset Sales of the
Partnership and its Restricted Subsidiaries since the Issue Date is in the form
of cash or Cash Equivalents. For purposes of this clause (c), each of the
following shall be deemed to be cash:


 


(i)            any liabilities (as shown on the Partnership’s most
recent consolidated balance sheet) of the Partnership or any Restricted
Subsidiary (other than contingent liabilities and liabilities that are by their
terms subordinated to the Notes or any Guarantee) that are assumed by the
transferee of any such assets pursuant to a customary novation agreement that
releases the Partnership or such Restricted Subsidiary from further liability;
and


 


(ii)           any securities, notes or other Obligations received by the
Partnership or any such Restricted Subsidiary from such transferee that are
within 90 days after the Asset Sale (subject to ordinary settlement periods)
converted by such Issuer or such Restricted Subsidiary into cash (to the extent
of the cash received in that conversion).


 


Within
360 days after the receipt of any Net Proceeds from an Asset Sale, the
Partnership or a Restricted Subsidiary may apply (or enter into a definitive
agreement for such application within such 360-day period, provided that such
application occurs within 90 days after the end of such 360-day period) such
Net Proceeds at its option:


 


47

















 


(a)           to
repay senior Indebtedness of the Partnership and/or its Restricted Subsidiaries
(or to make an offer to repurchase or redeem any such Indebtedness, provided
that such repurchase or redemption closes within 45 days after the end of such
360-day period);


 


(b)           to
make a capital expenditure in a Permitted Business;


 


(c)           to
acquire other long-term tangible assets that are used or useful in a Permitted
Business; or


 


(d)           to
invest in any other Permitted Business Investment or any other Permitted
Investments other than Investments in Cash Equivalents, Interest Swaps or
Currency Agreements.


 


Pending
the final application of any such Net Proceeds, the Partnership or a Restricted
Subsidiary may temporarily reduce revolving credit borrowings or otherwise
invest such Net Proceeds in any manner that is not prohibited by the Indenture.


 


Any
Net Proceeds from Asset Sales that are not applied or invested as provided in Section 5.07(b) above
will constitute “Excess Proceeds.” When the aggregate amount of Excess Proceeds
exceeds $25.0 million, within five days thereof the Partnership will make a pro
rata offer (an “Asset Sale Offer”) to all Holders of Notes and all holders of
other Indebtedness that is pari passu with the Notes containing provisions
similar to those set forth in the Indenture with respect to offers to purchase
or redeem with the proceeds of sales of assets to purchase the maximum
principal amount of Notes and such other pari passu Indebtedness that may be
purchased out of the Excess Proceeds. The offer price in any Asset Sale Offer
will be equal to 100% of principal amount plus accrued and unpaid interest, if
any, to the Purchase Date, subject to the rights of any Holder in whose name a
Note is registered on a record date occurring prior to the Purchase Date to
receive interest due on an Interest Payment Date that is on or prior to such
Purchase Date, and will be payable in cash. If any Excess Proceeds remain after
consummation of an Asset Sale Offer, the Partnership and its Restricted
Subsidiaries may use such Excess Proceeds for any purpose not otherwise
prohibited by the Indenture, including, without limitation, the repurchase or
redemption of Indebtedness of the Issuers or any Subsidiary Guarantor that is
subordinated to the Notes or, in the case of a Subsidiary Guarantor, the
Guarantee of such Subsidiary Guarantor. If the aggregate principal amount of
Notes tendered into such Asset Sale Offer exceeds the amount of Excess Proceeds
allocated for repurchases of Notes pursuant to the Asset Sale Offer for Notes,
the Trustee shall select the Notes to be purchased on a pro rata basis (or, in
the case of notes in global form, the Trustee will select Notes for redemption
based on DTC’s method that most nearly approximates a pro rata selection). Upon
completion of each Asset Sale Offer, the amount of Excess Proceeds shall be
reset at zero.


 


The
Partnership shall comply with the requirements of Rule 14e-1 under the
Exchange Act and any other securities laws and regulations thereunder to the
extent those laws and regulations are applicable in connection with each
repurchase of Notes pursuant to an Asset Sale Offer. To the extent that the
provisions of any securities laws or regulations conflict with Section


 


48
















 


4.09
or this Section 5.07, the Partnership shall comply with the applicable
securities laws and regulations and shall not be deemed to have breached its
obligations under Section 4.09 or this Section 5.07 by virtue of such
conflict.


 


Section 5.08           Restricted Payments.


 


The
Partnership shall not, and shall not permit any of its Restricted Subsidiaries
to, directly or indirectly:


 


(a)           declare
or pay any dividend or make any other payment or distribution on account of the
Partnership’s or any of its Restricted Subsidiaries’ Equity Interests
(including, without limitation, any payment in connection with any merger or
consolidation involving the Partnership or any of its Restricted Subsidiaries)
or to the direct or indirect holders of the Partnership’s or of any of its
Restricted Subsidiaries’ Equity Interests in their capacity as such (other than
dividends or distributions payable in Equity Interests of the Partnership
(other than Disqualified Equity) and other than dividends or distributions
payable to the Partnership or a Restricted Subsidiary of the Partnership);


 


(b)           purchase,
redeem or otherwise acquire or retire for value (including, without limitation,
in connection with any merger or consolidation involving an Issuer) any Equity
Interests of the Partnership or of any of its Restricted Subsidiaries (other
than any such Equity Interests owned by the Partnership or any of its
Restricted Subsidiaries);


 


(c)           make
any payment on or with respect to, or purchase, redeem, defease or otherwise
acquire or retire for value any Subordinated Obligation or Guarantor
Subordinated Obligation, except a payment of interest or principal at the
Stated Maturity thereof; or


 


(d)           make
any Investment other than a Permitted Investment or a Permitted Business
Investment (all such payments and other actions set forth in clauses (a) through
(d) above being collectively referred to as “Restricted Payments”);


 


unless,
at the time of and after giving effect to such Restricted Payment, no Default
(except a Reporting Default) or Event of Default shall have occurred and be
continuing or would occur as a consequence thereof and either:


 


(a)           if
the Fixed Charge Coverage Ratio for the Partnership’s four most recent fiscal
quarters for which internal financial statements are available is not less than
1.75 to 1.0, such Restricted Payment, together with the aggregate amount of all
other Restricted Payments made by the Partnership and its Restricted
Subsidiaries during the quarter in which such Restricted Payment is made, is
less than the sum, without duplication, of:


 


(i)            Available Cash as of the end of the immediately preceding
quarter, plus


 


(ii)           the sum of (1) the aggregate net cash proceeds of any
(A) substantially concurrent capital contribution to the Partnership from
any Person


 


49

















 


(other than to a Restricted Subsidiary of the
Partnership) made after the Issue Date or (B) substantially concurrent
issuance and sale (other than to a Restricted Subsidiary of the Partnership)
made after the Issue Date of Equity Interests (other than Disqualified Equity)
of the Partnership or from the issuance or sale (other than to a Restricted
Subsidiary of the Partnership) made after the Issue Date of convertible or
exchangeable Disqualified Equity or convertible or exchangeable debt securities
of the Partnership that have been converted into or exchanged for such Equity
Interests (other than Disqualified Equity), and (2) the fair market value
of any Permitted Business or long-term tangible assets that are useful in a
Permitted Business to the extent acquired in consideration of Equity Interests
of the Partnership (other than Disqualified Equity) since the Issue Date, plus


 


(iii)          to the extent that any Restricted Investment that was made
after the Issue Date is sold for cash or Cash Equivalents or otherwise
liquidated or repaid for cash or Cash Equivalents, the lesser of the refund of
capital or similar payment made in cash or Cash Equivalents with respect to
such Restricted Investment (less the cost of such disposition, if any) and the
initial amount of such Restricted Investment (other than to a Restricted
Subsidiary of the Partnership), plus


 


(iv)          the net reduction in Restricted Investments resulting from
dividends, repayments of loans or advances, or other transfers of assets in
each case to the Partnership or any of its Restricted Subsidiaries from any
Person (including, without limitation, Unrestricted Subsidiaries) or from
redesignations of Unrestricted Subsidiaries as Restricted Subsidiaries, to the
extent such amounts have not been included in Available Cash for any period
commencing on or after the Issue Date (items (ii), (iii) and (iv) of
this clause (a) being referred to as “Incremental Funds”), minus


 


(v)           the aggregate amount of Incremental Funds previously
expended pursuant to this clause (a) or clause (b) below; or


 


(b)           if
the Fixed Charge Coverage Ratio for the Partnership’s four most recent fiscal
quarters for which internal financial statements are available is less than
1.75 to 1.0, such Restricted Payment, together with the aggregate amount of all
other Restricted Payments made by the Partnership and its Restricted
Subsidiaries during the quarter in which such Restricted Payment is made (such
Restricted Payments for purposes of this clause (b) meaning only
distributions on common units of the Partnership, plus the related distribution
on the general partner interest) is less than the sum, without duplication, of:


 


(i)            $200.0 million less the aggregate amount of all prior
Restricted Payments made by the Partnership and its Restricted Subsidiaries
pursuant to this clause (b)(i) since the Issue Date, plus


 


(ii)           Incremental Funds to the extent not previously expended
pursuant to this clause (b) or clause (a) above.


 


50

















 


For
purposes of clauses (a) and (b) above, the term “substantially
concurrent” means that either (x) the offering was consummated within 120
days of the date of determination or (y) the offering was consummated
within 24 months of the date of determination and the proceeds therefrom were
used for the purposes expressly stated in the documents related thereto and may
be traced to such use by segregating, separating or otherwise specifically
identifying the movement of such proceeds.


 


So
long as no Default (except a Reporting Default) has occurred and is continuing
or would be caused thereby (except with respect to clause (a) below under
which the payment of a distribution or dividend is permitted), the preceding
provisions of this Section 5.08 shall not prohibit:


 


(a)           the
payment by the Partnership or any of its Restricted Subsidiaries of any
distribution or dividend within 60 days after the date of declaration thereof,
if at said date of declaration such payment would have complied with the
provisions of the Indenture;


 


(b)           the
redemption, repurchase, retirement, defeasance or other acquisition of any
Subordinated Obligation or any Guarantor Subordinated Obligation or of any
Equity Interests of the Partnership in exchange for, or out of the net cash
proceeds of, a substantially concurrent (i) capital contribution to the
Partnership from any Person (other than a Restricted Subsidiary of the
Partnership) or (ii) sale (other than to a Restricted Subsidiary of the
Partnership) of Equity Interests (other than Disqualified Equity) of the
Partnership (a sale will be deemed substantially concurrent if such redemption,
repurchase, retirement, defeasance or other acquisition occurs not more than
120 days after such sale); provided that the amount of any such net cash
proceeds that are utilized for any such redemption, repurchase, retirement,
defeasance or other acquisition shall be excluded or deducted from the
calculation of Available Cash and Incremental Funds;


 


(c)           the
redemption, repurchase, retirement, defeasance or other acquisition of any
Subordinated Obligation or Guarantor Subordinated Obligation with the net cash
proceeds from an incurrence of, or in exchange for, Permitted Refinancing
Indebtedness;


 


(d)           the
payment of any distribution or dividend by a Restricted Subsidiary to the
Partnership or to the holders of the Equity Interests (other than Disqualified
Equity) of such Restricted Subsidiary on a pro rata basis; and


 


(e)           the
repurchase, redemption or other acquisition or retirement for value of any Equity
Interests of the Partnership or any of its Restricted Subsidiaries pursuant to
any management equity subscription agreement or equity option agreement or
other employee benefit plan or to satisfy obligations under any Equity
Interests appreciation rights or option plan or similar arrangement; provided
that the aggregate price paid for all such repurchased, redeemed, acquired or
retired Equity Interests shall not exceed $3.0 million in any calendar year.


 


In
computing the amount of Restricted Payments previously made for purposes of Section 5.08,
Restricted Payments made under clauses (a) (but only if the declaration of
such


 


51

















 


dividend
or other distribution has not been counted in a prior period) and, to the
extent of amounts paid to holders other than the Partnership or any of its
Restricted Subsidiaries, clause (d) of this Section shall be
included, and Restricted Payments made under clauses (b), (c) and (e) and,
except to the extent noted above, clause (d) of this Section shall
not be included. The amount of all Restricted Payments (other than cash) shall
be the fair market value on the date of the Restricted Payment of the asset(s) or
securities proposed to be transferred or issued by the Partnership or such
Restricted Subsidiary, as the case may be, pursuant to the Restricted Payment.


 


Section 5.09           Incurrence of Indebtedness
and Issuance of Disqualified Equity.


 


(a)           The
Partnership shall not, and shall not permit any of its Restricted Subsidiaries
to, directly or indirectly, create, incur, issue, assume, guarantee or
otherwise become directly or indirectly liable, contingently or otherwise, with
respect to (collectively, “incur”) any Indebtedness (including Acquired Debt),
and the Partnership will not issue any Disqualified Equity and will not permit
any of its Restricted Subsidiaries to issue any Disqualified Equity; provided,
however, that the Partnership and any Restricted Subsidiary may incur
Indebtedness (including Acquired Debt), and the Partnership and the Restricted
Subsidiaries may issue Disqualified Equity, if the Fixed Charge Coverage Ratio
for the Partnership’s most recently ended four full fiscal quarters for which
internal financial statements are available immediately preceding the date on
which such additional Indebtedness is incurred or such Disqualified Equity is
issued would have been at least 2.0 to 1.0, determined on a pro forma basis
(including a pro forma application of the net proceeds therefrom), as if the
additional Indebtedness had been incurred, or the Disqualified Equity had been
issued, as the case may be, at the beginning of such four-quarter period.


 


(b)           Notwithstanding
the prohibitions of Section 5.09(a), the Partnership and its Restricted
Subsidiaries may incur any of the following items of Indebtedness
(collectively, “Permitted Debt”):


 


(i)            the incurrence by the Partnership and any Restricted
Subsidiary of Indebtedness under Credit Facilities and the guarantees thereof;
provided that the aggregate principal amount of all Indebtedness of the
Partnership and the Restricted Subsidiaries incurred pursuant to this clause (i) and
outstanding under all Credit Facilities after giving effect to such incurrence
does not exceed the greater of (A) $900.0 million or (B) $500.0
million plus 15.0% of the Consolidated Net Tangible Assets of the Partnership;


 


(ii)           the incurrence by the Partnership and its Restricted
Subsidiaries of Existing Indebtedness (other than under the Credit Facilities);


 


(iii)          the incurrence by the Issuers and the Subsidiary Guarantors
of Indebtedness represented by the Notes issued and sold in the offering of the
Initial Notes, and the related Guarantees;


 


52

















 


(iv)          the incurrence by the Partnership or any of its Restricted
Subsidiaries of Indebtedness represented by Capital Lease Obligations, mortgage
financings or purchase money obligations, in each case, incurred for the
purpose of financing all or any part of the purchase price or cost of
construction or improvement of property, plant or equipment used in the
business of the Partnership or such Restricted Subsidiary, including all
Permitted Refinancing Indebtedness incurred to extend, refinance, renew,
replace, defease or refund any Indebtedness incurred pursuant to this clause
(iv), provided that after giving effect to any such incurrence, the principal
amount of all Indebtedness incurred pursuant to this clause (iv) and then
outstanding shall not exceed the greater of (a) $25.0 million or (b) 1.0%
of the Consolidated Net Tangible Assets of the Partnership at such time;


 


(v)           the incurrence by the Partnership or any of its Restricted
Subsidiaries of Permitted Refinancing Indebtedness in exchange for, or the net
proceeds of which are used to extend, refinance, renew, replace, defease or
refund, Indebtedness that was permitted by the Indenture to be incurred
under Section 5.09(a) or clause (ii) or (iii) of this Section 5.09(b) or
this clause (v);


 


(vi)          the incurrence by the Partnership or any of its Restricted
Subsidiaries of intercompany Indebtedness between or among the Partnership and
any of its Restricted Subsidiaries; provided, however, that:


 


(A)          if the Partnership is the obligor on such Indebtedness and
a Subsidiary Guarantor is not the obligee, such Indebtedness must be expressly
subordinated to the prior payment in full in cash of all Obligations with
respect to the Notes, or if a Subsidiary Guarantor is the obligor on such
Indebtedness and neither the Partnership nor another Subsidiary Guarantor is
the obligee, such Indebtedness must be expressly subordinated to the prior
payment in full in cash of all Obligations with respect to the Guarantee of
such Subsidiary Guarantor; and


 


(B)           (i) any subsequent issuance or transfer of Equity
Interests that results in any such Indebtedness being held by a Person other
than the Partnership or a Restricted Subsidiary thereof and (ii) any sale
or other transfer of any such Indebtedness to a Person that is neither the
Partnership nor a Restricted Subsidiary thereof, shall be deemed, in each case,
to constitute an incurrence of such Indebtedness by the Partnership or such
Restricted Subsidiary, as the case may be, that was not permitted by this
clause (vi);


 


(vii)         the incurrence by the Partnership or any of its Restricted
Subsidiaries of Hedging Obligations that are incurred for the purpose of fixing
or hedging (but not for speculative purposes) (A) foreign currency
exchange rate risks of the Partnership or any Restricted Subsidiary, (B) interest
rate risks with


 


53

















 


respect to any floating rate Indebtedness of the
Partnership or any Restricted Subsidiary that is permitted by the terms of the
Indenture to be outstanding or (C) commodities pricing risks of the
Partnership or any Restricted Subsidiary in respect of Hydrocarbons used,
produced, processed or sold by the Partnership or any of its Restricted
Subsidiaries;


 


(viii)        the guarantee by the Partnership or any
of its Restricted Subsidiaries of Indebtedness of the Partnership or any of its
Restricted Subsidiaries that was permitted to be incurred by another provision
of this Section 5.09; provided, that in the event such Indebtedness that
is being guaranteed is a Subordinated Obligation or a Guarantor Subordinated
Obligation, then the guarantee shall be subordinated in right of payment to the
Notes or the Guarantee, as the case may be;


 


(ix)           bid, performance, surety and appeal bonds incurred in the
ordinary course of business, including guarantees and obligations respecting
standby letters of credit supporting such obligations, to the extent not drawn
(in each case other than an obligation for money borrowed);


 


(x)            the incurrence by the Partnership or any of its
Restricted Subsidiaries of liability in respect of the Indebtedness of any
Unrestricted Subsidiary of the Partnership or any Joint Venture but only to the
extent that such liability is the result of the Partnership’s or any such
Restricted Subsidiary’s being a general partner of such Unrestricted Subsidiary
or Joint Venture and not as guarantor of such Indebtedness and provided that,
after giving effect to any such incurrence, the aggregate principal amount of
all Indebtedness incurred under this clause (x) and then outstanding does
not exceed $25.0 million;


 


(xi)           the incurrence by the Partnership or any of its Restricted
Subsidiaries of Acquired Debt in connection with a merger or consolidation
meeting either one of the financial tests set forth in clause (iv) of Section 6.01(a);
and


 


(xii)          the incurrence by the Partnership or any of its Restricted
Subsidiaries of additional Indebtedness in an aggregate principal amount at any
time outstanding not to exceed the greater of (a) $100.0 million or (b) 4.0%
of the Consolidated Net Tangible Assets of the Partnership.


 


(c)           For
purposes of determining compliance with this Section 5.09, in the event
that an item of proposed Indebtedness meets the criteria of more than one of
the categories of Permitted Debt described in paragraphs (b)(i) through
(b)(xii) above, or is entitled to be incurred pursuant to Section 5.09(a),
the Partnership shall be permitted to classify (or later reclassify in whole or
in part) such item of Indebtedness on the date of its incurrence in any manner
that complies with this Section 5.09. 
An item of Indebtedness may be divided and


 


54

















 


classified
in one or more of the types of Permitted Indebtedness.  Any Indebtedness under Credit Facilities on
the Issue Date shall be considered incurred under Section 5.09(a).


 


(d)           The
accrual of interest, the accretion or amortization of original issue discount,
the payment of interest on any Indebtedness in the form of additional
Indebtedness with the same terms, and the payment of dividends on Disqualified
Equity in the form of additional shares of the same class of Disqualified
Equity shall not be deemed to be an incurrence of Indebtedness or an issuance
of Disqualified Equity for purposes of this Section 5.09; provided, in
each such case, that the amount thereof is included in Fixed Charges of the
Partnership as accrued. Notwithstanding any other provision of this Section 5.09,
the maximum amount of Indebtedness that the Partnership or any Restricted
Subsidiary may incur pursuant to this covenant shall not be deemed to be
exceeded solely as a result of fluctuations in exchange rates or currency
values. Further, the accounting reclassification of any obligation of the
Partnership or any of its Restricted Subsidiaries as Indebtedness will not be
deemed an incurrence of Indebtedness for purposes of this Section 5.09.


 


Section 5.10           Liens.


 


The
Partnership shall not, and shall not permit any of its Restricted Subsidiaries
to create, incur, assume or suffer to exist any Lien of any kind securing
Indebtedness upon any asset now owned or hereafter acquired, except Permitted
Liens, without making effective provision whereby all Obligations due under the
Notes and the Indenture or any Guarantee, as applicable, will be secured by a
Lien equally and ratably with (or prior to in the case of Liens with respect to
Subordinated Obligations or Guarantor Subordinated Obligations, as the case may
be) any and all Obligations thereby secured for so long as any such Obligations
shall be so secured.


 


Section 5.11           Dividend and Other Payment
Restrictions Affecting Subsidiaries.


 


(a)           The
Partnership shall not, and shall not permit any of its Restricted Subsidiaries
to, directly or indirectly, create or permit to exist or become effective any
encumbrance or restriction on the ability of any Restricted Subsidiary to:


 


(i)            pay dividends or make any other distributions on its
Equity Interests to the Partnership or any of the Partnership’s Restricted
Subsidiaries, or pay any indebtedness or other obligations owed to the
Partnership or any of the other Restricted Subsidiaries;


 


(ii)           make loans or advances to or make other Investments in the
Partnership or any of the other Restricted Subsidiaries; or


 


(iii)          transfer any of its properties or assets to the Partnership
or any of the other Restricted Subsidiaries.


 


(b)           The
restrictions contained in Section 5.11(a) shall not apply to
encumbrances or restrictions existing under or by reason of:


 


55

















 


(i)            agreements as in
effect on the Issue Date and any amendments, modifications, restatements,
renewals, increases, supplements, refundings, replacements or refinancings of
any such agreements or any Existing Indebtedness to which such agreement relates, provided that such
amendments, modifications, restatements, renewals, increases, supplements, refundings,
replacements or refinancings are no more restrictive, taken as a whole, with
respect to such distribution, dividend and other payment restrictions
and loan or investment restrictions than those contained in such agreement, as
in effect on the Issue Date;


 


(ii)           the Indenture, the Notes and the
Guarantees;


 


(iii)          applicable law;


 


(iv)          any instrument governing Indebtedness
or Equity Interests of a Person acquired by the Partnership or any of its
Restricted Subsidiaries as in effect at the time of such acquisition (except to
the extent such Indebtedness was incurred in connection with or in
contemplation of such acquisition), which encumbrance or restriction is not
applicable to any Person, or the property or assets of any Person, other than
such Person, or the property or assets of such Person, so acquired, provided
that, in the case of Indebtedness, such Indebtedness was permitted by the terms
of the Indenture to be incurred;


 


(v)           customary non-assignment provisions
in agreements for the purchase, gathering, processing, sale, transportation or
exchange of Hydrocarbons or similar operational agreements or in licenses,
leases, rights-of-way or other easements or servitudes, in each case entered
into in the ordinary course of business;


 


(vi)          Capital Lease Obligations, mortgage
financings or purchase money obligations, in each case for property acquired in
the ordinary course of business that impose restrictions on the property so
acquired of the nature described in clause (iii) of Section 5.11(a);


 


(vii)         any agreement for the sale or other
disposition of a Restricted Subsidiary that restricts distributions by that
Restricted Subsidiary pending its sale or other disposition;


 


(viii)        Permitted Refinancing Indebtedness,
provided that the restrictions contained in the agreements governing such
Permitted Refinancing Indebtedness are no more restrictive, taken as a whole,
than those contained in the agreements governing the Indebtedness being
refinanced;


 


(ix)           Liens securing Indebtedness otherwise
permitted to be incurred pursuant to the provisions of Section 5.10 that
limit the right of the Partnership or any of its Restricted Subsidiaries to
dispose of the assets subject to such Lien;


 


56

















 


(x)            provisions with respect to the
disposition or distribution of assets or property in joint venture agreements,
asset sale agreements, stock sale agreements and other similar agreements
entered into in the ordinary course of business;


 


(xi)           any agreement or instrument
relating to any property or assets acquired after the Issue Date, so long as
such encumbrance or restriction relates only to the property or assets so
acquired and is not and was not created in anticipation of such acquisitions;


 


(xii)          restrictions on cash or
other deposits or net worth imposed by customers under contracts entered into
in the ordinary course of business;


 


(xiii)         with respect to any Foreign Subsidiary,
any encumbrance or restriction contained in the terms of any Indebtedness or
any agreement pursuant to which such Indebtedness was incurred if either (a) the
encumbrance or restriction applies only in the event of a payment default or a
default with respect to a financial covenant in such Indebtedness or agreement
or (b) the Partnership determines that any such encumbrance or restriction
will not materially affect the Issuers’ ability to make principal or interest
payments on the Notes, as determined in good faith by the Board of Directors of
the General Partner, whose determination shall be conclusive; and


 


(xiv)        any other agreement
governing Indebtedness of the Partnership or any Restricted Subsidiary that is
permitted to be incurred by Section 5.12; provided, however, that such
encumbrances or restrictions are not materially more restrictive, taken as a
whole, than those contained in the Indenture or the Credit Agreement as it
exists on the Issue Date.


 


Section 5.12           Transactions With
Affiliates.


 


The
Partnership shall not, and shall not permit any of its Restricted Subsidiaries
to, make any payment to, or sell, lease, transfer or otherwise dispose of any
of its properties or assets to, or purchase any property or assets from, or
enter into or make or amend any transaction, contract, agreement,
understanding, loan, advance or guarantee with, or for the benefit of, any
Affiliate (each, an “Affiliate Transaction”), unless:


 


(a)           such
Affiliate Transaction is on terms that are no less favorable to the Partnership
or the relevant Restricted Subsidiary than those that would have been obtained
in a comparable transaction by the Partnership or such Restricted Subsidiary
with an unrelated Person; and


 


(b)           the
Partnership delivers to the Trustee:


 


(i)            with respect to any Affiliate Transaction or series of
related Affiliate Transactions involving aggregate consideration in excess of
$10.0 million


 


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but less than or equal to $30.0 million, an Officers’
Certificate certifying that such Affiliate Transaction complies with this Section 5.12
and that such Affiliate Transaction has been approved by a majority of the
disinterested members of the Board of Directors of the General Partner; and


 


(ii)           with respect to any Affiliate Transaction or series of
related Affiliate Transactions involving aggregate consideration in excess of
$30.0  million, a resolution of the Board of
Directors of the General Partner set forth in an Officers’ Certificate
certifying that such Affiliate Transaction complies with this Section 5.12
and that such Affiliate Transaction has been approved by a majority of the
disinterested members of the Board of Directors of the General Partner.


 


The
following items shall not be deemed to be Affiliate Transactions and,
therefore, shall not be subject to the provisions of Section 5.11(a):


 


(a)           any
employment, equity option or equity appreciation agreement or plan entered into
by the Partnership or any of its Restricted Subsidiaries in the ordinary course
of business;


 


(b)           transactions
between or among the Partnership and/or its Restricted Subsidiaries;


 


(c)           Permitted
Investments or Restricted Payments that are permitted by Section 5.08;


 


(d)           customary
compensation, indemnification and other benefits made available to officers,
directors or employees of the Partnership or a Restricted Subsidiary, including
reimbursement or advancement of out-of-pocket expenses and provisions of
officers’ and directors’ liability insurance;


 


(e)           sales
of Equity Interests (other than Disqualified Equity) to Affiliates of the
Partnership;


 


(f)            in
the case of contracts for gathering, transporting, treating, processing,
marketing, distributing, storing or otherwise handling Hydrocarbons, or
activities or services reasonably related or ancillary thereto, or other
operational contracts, any such contracts are entered into in the ordinary
course of business on terms substantially similar to those contained in similar
contracts entered into by the Partnership or any Restricted Subsidiary and
third parties; and


 


(g)           transactions
with a Person (other than an Unrestricted Subsidiary of the Partnership) that
is an Affiliate of the Partnership solely because the Partnership owns an
Equity Interest in such Person.


 


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Section 5.13           Additional Subsidiary
Guarantees.


 


If,
after the Issue Date, any Restricted Subsidiary of the Partnership that is not
already a Subsidiary Guarantor guarantees any other Indebtedness of either of
the Issuers or any Indebtedness of the Operating Company, or if the Operating
Company, if not then a Subsidiary Guarantor, guarantees any other Indebtedness
of either of the Issuers or incurs any Indebtedness under any Credit Facility,
then in either case such Subsidiary must become a Subsidiary Guarantor by
executing a supplemental indenture substantially in the form of Exhibit C
hereto and delivering an Opinion of Counsel to the Trustee pursuant to Section 10.06
within 10 Business Days of the date on which it guaranteed or incurred such
Indebtedness.  Notwithstanding the
preceding, any Guarantee of a Restricted Subsidiary that was incurred pursuant
to this Section 5.13 shall be released in accordance with the terms and
subject to the conditions of Section 11.04.


 


Section 5.14           Designation of Restricted
and Unrestricted Subsidiaries.


 


(a)           The
Board of Directors of the General Partner may designate any Restricted
Subsidiary of the Partnership to be an Unrestricted Subsidiary if that
designation would not cause a Default or Event of Default.  If a Restricted Subsidiary is designated as
an Unrestricted Subsidiary, all outstanding Investments owned by the
Partnership and its Restricted Subsidiaries in the Subsidiary so designated
will be deemed to be an Investment made as of the time of such designation and
will reduce the amount available for Restricted Payments under Section 5.08(a),
or represent Permitted Investments or Permitted Business Investments, as
applicable.  All such outstanding
Investments will be valued at their fair market value at the time of such
designation.  That designation will only
be permitted if such Restricted Payment, Permitted Investments or Permitted
Business Investments would be permitted under the Indenture at that time and
such Restricted Subsidiary otherwise complies with the definition of an
Unrestricted Subsidiary.  All Subsidiaries
of an Unrestricted Subsidiary shall also be Unrestricted Subsidiaries.  Upon the designation of a Restricted
Subsidiary that is a Subsidiary Guarantor as an Unrestricted Subsidiary, the
Guarantee of such entity shall be released and the Trustee shall be authorized
to take such actions as may be appropriate to reflect such release.


 


(b)           The
Board of Directors of the General Partner may at any time designate any
Unrestricted Subsidiary to be a Restricted Subsidiary; provided that such
designation shall be deemed to be an incurrence of Indebtedness by a Restricted
Subsidiary of the Partnership of any outstanding Indebtedness of such
Unrestricted Subsidiary and such designation shall only be permitted if (1) such
Indebtedness is permitted under Section 5.09, calculated on a pro forma
basis as if such designation had occurred at the beginning of the four-quarter
reference period; and (2) no Default or Event of Default would be in
existence following such designation.


 


Section 5.15           Business Activities.


 


The
Partnership shall not, and shall not permit any of its Restricted Subsidiaries
to, engage in any business other than Permitted Businesses, except to such
extent as would not be material to the Partnership and its Restricted
Subsidiaries, taken as a whole.


 


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MarkWest
Finance shall not incur Indebtedness unless (a) the Partnership is a
co-obligor or guarantor of such Indebtedness or (b) the net proceeds of
such Indebtedness are loaned to the Partnership, used to acquire outstanding
debt securities issued by the Partnership or used to repay Indebtedness of the
Partnership as permitted under Section 5.09.  MarkWest Finance shall not engage in any
business not related directly or indirectly to obtaining money or arranging
financing for the Partnership or its Restricted Subsidiaries.


 


Section 5.16           Sale and Leaseback
Transactions.


 


The
Partnership shall not, and shall not permit any of its Restricted Subsidiaries
to, enter into any sale and leaseback transaction; provided that the
Partnership or any Restricted Subsidiary may enter into a sale and leaseback
transaction if:


 


(a)           the
Partnership or that Restricted Subsidiary, as applicable, could have (i) incurred
Indebtedness in an amount equal to the Attributable Debt relating to such sale
and leaseback transaction under Section 5.09(a), and (ii) incurred a
Lien to secure such Indebtedness pursuant to Section 5.10;


 


(b)           the
gross cash proceeds of that sale and leaseback transaction are at least equal
to the fair market value of the property that is the subject of such sale and
leaseback transaction; and


 


(c)           the
transfer of assets in that sale and leaseback transaction is permitted by, and
the Partnership applies the proceeds of such transaction in compliance with,
the provisions set forth under Sections 4.09 and 5.07.


 


Section 5.17           Payments for Consent.


 


The
Partnership shall not, and shall not permit any of its Subsidiaries to,
directly or indirectly, pay or cause to be paid any consideration to or for the
benefit of any Holder of Notes for or as an inducement to any consent, waiver
or amendment of any of the terms or provisions of the Indenture or the Notes
unless such consideration is offered to be paid and is paid to all Holders of
the Notes that consent, waive or agree to amend in the time frame set forth in
the solicitation documents relating to such consent, waiver or agreement.


 


Section 5.18           Reports.


 


Whether
or not required by the SEC, so long as any Notes are outstanding, the
Partnership will file with the SEC (unless the SEC will not accept such a filing)
within the time periods specified in the SEC’s rules and regulations, and
upon request, the Partnership will furnish (without exhibits) to the Trustee
for delivery to the Holders of Notes:


 


(a)           all
quarterly and annual financial information that would be required to be
contained in a filing with the SEC on Forms 10-Q and 10-K if the Partnership
were required to file such forms, including a “Management’s Discussion and
Analysis of Financial Condition and


 


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Results
of Operations” and, with respect to the annual information only, a report on
the annual financial statements by the Partnership’s certified independent
accountants; and


 


(b)           all
current reports that would be required to be filed with the SEC on Form 8-K
if the Partnership were required to file such reports.


 


The
availability of the foregoing information or reports on the SEC’s website will
be deemed to satisfy the foregoing delivery requirements.


 


If as of the end of any such quarterly or annual period
referred to in Section 5.18(a), the Partnership has designated any of its
Subsidiaries as Unrestricted Subsidiaries, then the Partnership shall deliver
(promptly after such SEC filing referred to in Section 5.18(a)) to the
Trustee for delivery to the Holders of the Notes quarterly and annual financial
information required by Section 5.18(a) as revised to include a
reasonably detailed presentation, either on the face of the financial
statements or in the footnotes thereto, and in “Management’s Discussion and
Analysis of Financial Condition and Results of Operations,” of the financial
condition and results of operations of the Partnership and its Restricted Subsidiaries
separate from the financial condition and results of operations of the
Unrestricted Subsidiaries of the Partnership.


 


Whether or not required by the SEC, the
Partnership will make such information available to securities analysts,
investors and prospective investors upon request.  In addition, upon request the Partnership
shall furnish the Trustee such other non-confidential information, documents
and other reports which the Partnership is required to file with the SEC
pursuant to Section 13 or Section 15(d) of the Exchange Act.


 


Delivery
of reports, information and documents to the Trustee pursuant to this Section 5.18
is for informational purposes only and the Trustee’s receipt of such shall not
constitute constructive notice of any information contained therein or
determinable from information contained therein, including the Partnership’s
compliance with any of its covenants hereunder (as to which the Trustee is
entitled to rely exclusively on Officers’ Certificates).


 


Section 5.19           Termination of Covenants


 


If
at any time (a) the Notes have an Investment Grade Rating from both Rating
Agencies, (b) no Default has occurred and is continuing and (c) the
Issuers have delivered to the Trustee an Officers’ Certificate certifying to (a) and
(b) of this Section 5.19, the Partnership and its Restricted
Subsidiaries shall no longer be subject to the provisions of Sections 4.09,
5.07, 5.08, 5.09, 5.11, 5.12, 5.15, clauses (a)(i) and (c) of Section 5.16,
and clause (a)(iv) of Section 6.01 of the Indenture.  However, the Partnership and its Restricted
Subsidiaries will remain subject to all of the other provisions of the
Indenture.


 


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ARTICLE VI

SUCCESSORS


 


Section 6.01           Merger, Consolidation, or
Sale of Assets.


 


(a)           Neither
of the Issuers may, directly or indirectly: (x) consolidate or merge with
or into another Person (whether or not such Issuer is the survivor); or (y) sell,
assign, transfer, lease, convey or otherwise dispose of all or substantially
all of its properties or assets, in one or more related transactions, to
another Person; unless:


 


(i)            either: (A) such Issuer is the surviving entity of
such transaction; or (B) the Person formed by or surviving any such
consolidation or merger (if other than such Issuer) or to which such sale,
assignment, transfer, lease, conveyance or other disposition shall have been
made is an entity organized or existing under the laws of the United States,
any state thereof or the District of Columbia, provided that MarkWest Finance
may not consolidate or merge with or into any entity other than a corporation
satisfying such requirement for so long as the Partnership remains a
partnership;


 


(ii)           the Person formed by or surviving any such consolidation
or merger (if other than such Issuer) or the Person to which such sale,
assignment, transfer, lease, conveyance or other disposition shall have been
made expressly assumes all the obligations of such Issuer under the Notes and
the Indenture pursuant to agreements reasonably satisfactory to the Trustee;


 


(iii)          immediately after such transaction no Default or Event of
Default exists;


 


(iv)          in the case of a transaction involving the Partnership and
not MarkWest Finance, either:


 


(A)          the Partnership or the Person formed by or surviving any
such consolidation or merger (if other than the Partnership), or to which such
sale, assignment, transfer, lease, conveyance or other disposition has been
made shall, on the date of such transaction after giving pro forma effect
thereto and any related financing transactions as if the same had occurred at
the beginning of the applicable four-quarter period, be permitted to incur at
least $1.00 of additional Indebtedness pursuant to the Fixed Charge Coverage
Ratio test set forth in Section 5.09(a); or


 


(B)           immediately after giving effect to such transaction on a
pro forma basis and any related financing transactions as if the same had
occurred at the beginning of the applicable four-quarter period, the Fixed
Charge Coverage Ratio of the Partnership or the Person formed by or surviving
any such consolidation or merger (if other than the Partnership) or to which
such sale, assignment, transfer, lease, conveyance or other


 


62

















 


disposition has been made, will be equal to or
greater than the Fixed Charge Coverage Ratio of the Partnership immediately
before such transactions; and


 


(v)           such Issuer has delivered to the Trustee an Officers’
Certificate and an Opinion of Counsel, each stating that such consolidation,
merger or disposition and, if a supplemental indenture is required, such
supplemental indenture comply with the Indenture and all conditions precedent
therein relating to such transaction have been satisfied.


 


(b)           Notwithstanding
Section 6.01(a), the Partnership is permitted to reorganize as any other
form of entity in accordance with the procedures established in the Indenture;
provided that:


 


(i)            the reorganization involves the conversion (by merger,
sale, contribution or exchange of assets or otherwise) of the Partnership into
a form of entity other than a limited partnership formed under Delaware law;


 


(ii)           the entity so formed by or resulting from such
reorganization is an entity organized or existing under the laws of the United
States, any state thereof or the District of Columbia;


 


(iii)          the entity so formed by or resulting from such reorganization
assumes all of the obligations of the Partnership under the Notes and the
Indenture pursuant to agreements reasonably satisfactory to the Trustee;


 


(iv)          immediately after such reorganization no Default or Event
of Default exists; and


 


(v)           such reorganization is not adverse to the Holders of the
Notes (for purposes of this clause (v) it is stipulated that such
reorganization shall not be considered adverse to the Holders of the Notes
solely because the successor or survivor of such reorganization (A) is
subject to federal or state income taxation as an entity or (B) is
considered to be an “includible corporation” of an affiliated group of
corporations within the meaning of Section 1504(b)(i) of the Code or
any similar state or local law).


 


(c)           No
Subsidiary Guarantor may consolidate with or merge with or into (whether or not
such Subsidiary Guarantor is the surviving Person) another Person, except the
Partnership or another Subsidiary Guarantor, unless (i) immediately after
giving effect to such transaction, no Default or Event of Default exists, and (ii) the
Person formed by or surviving any such consolidation or merger assumes all the
obligations of such Subsidiary Guarantor pursuant to the Subsidiary Guarantor’s
Guarantee of the Notes and the Indenture pursuant to a supplemental indenture
substantially in the form of Exhibit C hereto, except that no such
assumption or supplemental indenture shall be required in those circumstances
described in clauses (i) and (ii) of Section 11.05 hereof.  In case of any such consolidation or merger
and


 


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upon
the assumption by the successor Person by supplemental indenture, executed and
delivered to the Trustee substantially in the form of Exhibit C
hereto, of the Guarantees contained herein and the due and punctual performance
of all of the covenants of the Indenture to be performed by the Subsidiary
Guarantor, such successor shall succeed to and be substituted for the
Subsidiary Guarantor with the same effect as if it had been named herein as a
Subsidiary Guarantor.  Such successor
thereupon may cause to be signed any or all of the notations of the Guarantees
to be endorsed upon all of the Notes issuable hereunder which theretofore shall
not have been signed by the Issuers and delivered to the Trustee.  All the Guarantees so issued shall in all
respects have the same legal rank and benefit under the Indenture as the
Guarantees theretofore and thereafter issued in accordance with the terms of
the Indenture as though all of such Guarantees had been issued at the date of
the execution hereof.


 


Section 6.02           Successor Entity
Substituted.


 


(a)           Upon
any consolidation or merger, or any sale, assignment, transfer, lease,
conveyance or other disposition of all or substantially all of the properties
or assets of an Issuer in accordance with Section 6.01 hereof, the
surviving entity formed by such consolidation or into or with which such Issuer
is merged or to which such sale, assignment, transfer, lease, conveyance or
other disposition is made shall succeed to, and be substituted for (so that
from and after the date of such consolidation, merger, sale, assignment,
transfer, lease, conveyance or other disposition, the provisions of the
Indenture referring to the “Partnership” or “MarkWest Finance,” as the case may
be, shall refer instead to the surviving entity and not to the Partnership or
MarkWest Finance, as the case may be), and may exercise every right and power
of the Partnership or MarkWest Finance, as the case may be, under the Indenture
with the same effect as if such successor Person had been named as an Issuer
herein; and thereafter, if an Issuer is dissolved following a disposition of
all or substantially all of its properties or assets in accordance with the
Indenture, it shall be discharged and released from all obligations and
covenants under the Indenture and the Notes; provided, however, that the
predecessor shall not be relieved from the obligation to pay the principal of
and interest on the Notes in the case of a lease of all or substantially all of
its properties or assets.


 


(b)           If
the surviving entity shall have succeeded to and been substituted for an
Issuer, such surviving entity may cause to be signed, and may issue either in
its own name or in the name of the applicable Issuer prior to such succession
any or all of the Notes issuable hereunder which theretofore shall not have
been signed by such Issuer and delivered to the Trustee; and, upon the order of
such surviving entity, instead of such Issuer, and subject to all the terms,
conditions and limitations in the Indenture prescribed, the Trustee shall
authenticate and shall deliver any Notes which previously shall have been
signed and delivered by the Officers of such Issuer to the Trustee for
authentication, and any Notes which such surviving entity thereafter shall
cause to be signed and delivered to the Trustee for that purpose (in each
instance with notations of Guarantees thereon by the Subsidiary
Guarantors).  All of the Notes so issued
and so endorsed shall in all respects have the same legal rank and benefit
under the Indenture as the Notes theretofore or thereafter issued and endorsed
in accordance with the terms of the Indenture and the Guarantees as though all
such Notes had been issued and endorsed at the date of the execution hereof.


 


64

















 


(c)           In
case of any such consolidation, merger, sale, assignment, transfer, lease,
conveyance or other disposition, such changes in phraseology and form (but not
in substance) may be made in the Notes thereafter to be issued or the
Guarantees to be endorsed thereon as may be appropriate.


 


(d)           For
all purposes of the Indenture and the Notes, Subsidiaries of any surviving
entity (other than an Issuer) will, upon such transaction or series of
transactions, become Restricted Subsidiaries or Unrestricted Subsidiaries as
provided pursuant to the Indenture and all Indebtedness, and all Liens on
property or assets, of such surviving entity and its Restricted Subsidiaries
immediately prior to such transaction or series of transactions shall be deemed
to have been incurred upon such transaction or series of transactions.


 


ARTICLE VII

DEFAULTS AND REMEDIES


 


Section 7.01           Events of Default.


 


Each
of the following is an “Event of Default”:


 


(a)           default
for 30 days in the payment when due of interest on the Notes;


 


(b)           default
in payment when due of the principal of or premium, if any, on the Notes;


 


(c)           failure
by the Partnership  to comply with the
provisions described under Section 6.01 hereof;


 


(d)           failure
by the Partnership to comply with the provisions described under Section 5.18
hereof for 90 days after notice to the Issuers by the Trustee or to the Issuers
and Trustee by Holders of at least 25% in aggregate principal amount of the
Notes then outstanding;


 


(e)           subject
to Section 5.19, failure by the Partnership to comply with the provisions
described under Section 4.09, 5.06, 5.07, 5.08, 5.09, 5.10, 5.11. 5.12,
5.13, 5.14, 5.15, 5.16 or 5.17 hereof for 30 days after notice to the Issuers by
the Trustee or to the Issuers and Trustee by Holders of at least 25% in
aggregate principal amount of the Notes then outstanding (provided that no such
notice need be given, and an Event of Default shall occur, 30 days after a
failure to comply with the covenants in Section 5.08 or 5.09 hereof,
unless theretofore cured), in each case other than a failure to purchase Notes
which will constitute an Event of Default under clause (b) of this Section 7.01;


 


(f)            failure
by the Partnership to comply with any of its other agreements in the Indenture
for 60 days after notice to the Issuers by the Trustee or to the Issuers and
Trustee by Holders of at least 25% in aggregate principal amount of the Notes
then outstanding;


 


(g)           default
under any mortgage, indenture or instrument under which there may be issued or
by which there may be secured or evidenced any Indebtedness for money


 


65

















 


borrowed
by either Issuer or any of the Restricted Subsidiaries of the Partnership (or
the payment of which is guaranteed by either Issuer or any of such Restricted
Subsidiaries), whether such Indebtedness or guarantee now exists or is created
after the date of this Supplemental Indenture, if that default:


 


(i)            is caused by a failure to pay principal of or premium, if
any, or interest on such Indebtedness prior to the expiration of the grace
period provided in such Indebtedness (a “Payment Default”), or


 


(ii)           results in the acceleration of such Indebtedness prior to
its express maturity,


 


and,
in each case, the principal amount of any such Indebtedness, together with the
principal amount of any other such Indebtedness under which there has been a
Payment Default or the maturity of which has been so accelerated, aggregates
$20.0 million or more; provided that if any such default is cured or waived or
any such acceleration rescinded, or such Indebtedness is repaid, within a
period of 30 days from the continuation of such default beyond the applicable
grace period or the occurrence of such acceleration, as the case may be, such
Event of Default and any consequential acceleration of the Notes shall be
automatically rescinded, so long as such rescission does not conflict with any
judgment or decree;


 


(h)           failure
by an Issuer or any Restricted Subsidiary of the Partnership to pay final
judgments entered by a court of competent jurisdiction aggregating in excess of
$20.0 million, which judgments are not paid, discharged or stayed for a period
of 60 days;


 


(i)            except
as permitted by the Indenture, any Guarantee shall be held in any judicial
proceeding to be unenforceable or invalid or shall cease for any reason to be
in full force and effect or any Subsidiary Guarantor, or any Person acting on
behalf of a Subsidiary Guarantor, shall deny or disaffirm its obligations under
its Guarantee;


 


(j)            either
Issuer or any Restricted Subsidiary of the Partnership that is a Significant
Subsidiary or any group of Restricted Subsidiaries of the Partnership that,
taken as a whole, would constitute a Significant Subsidiary, pursuant to or
within the meaning of Bankruptcy Law:


 


(i)            commences a voluntary case,


 


(ii)           consents to the entry of an order for relief against it in
an involuntary case,


 


(iii)          consents to the appointment of a custodian of it or for all
or substantially all of its property,


 


(iv)          makes a general assignment for the benefit of its
creditors, or


 


66

















 


(v)           generally is not paying its debts as they become due; and


 


(k)           a
court of competent jurisdiction enters an order or decree under any Bankruptcy
Law that:


 


(i)            is for relief against an Issuer or any Restricted
Subsidiary of the Partnership that is a Significant Subsidiary or any group of
Restricted Subsidiaries of the Partnership that, taken as a whole, would
constitute a Significant Subsidiary in an involuntary case;


 


(ii)           appoints a custodian of an Issuer or any Restricted
Subsidiary of the Partnership that is a Significant Subsidiary or any group of
Restricted Subsidiaries of the Partnership that, taken as a whole, would
constitute a Significant Subsidiary or for all or substantially all of the
property of an Issuer or any Restricted Subsidiary of the Partnership that is a
Significant Subsidiary or any group of Restricted Subsidiaries of the
Partnership that, taken as a whole, would constitute a Significant Subsidiary;
or


 


(iii)          orders the liquidation of an Issuer or any Restricted
Subsidiary of the Partnership that is a Significant Subsidiary or any group of
Restricted Subsidiaries of the Partnership that, taken as a whole, would
constitute a Significant Subsidiary;


 


and
the order or decree remains unstayed and in effect for 60 consecutive days.


 


Section 7.02           Acceleration.


 


If
any Event of Default (other than an Event of Default specified in clause (j) or
(k) of Section 7.01 hereof) occurs and is continuing, the Trustee
may, and upon written request of the Holders of at least 25% in aggregate
principal amount of the then outstanding Notes shall, declare all the Notes to
be due and payable immediately.  Upon any
such declaration, the Notes shall become due and payable immediately.  Notwithstanding the foregoing, if an Event of
Default specified in clause (j) or (k) of Section 7.01 hereof
occurs with respect to an Issuer, all outstanding Notes shall be due and payable
immediately without further action or notice. 
The Holders of a majority in aggregate principal amount of the then
outstanding Notes by written notice to the Trustee may on behalf of the Holders
of all of the Notes rescind an acceleration and its consequences if the
rescission would not conflict with any judgment or decree and if all existing
Events of Default (except nonpayment of principal, interest or premium that has
become due solely because of the acceleration) have been cured or waived.


 


Section 7.03           Other Remedies.


 


If
an Event of Default occurs and is continuing, the Trustee may pursue any
available remedy to collect the payment of principal, premium, if any, and
interest on the Notes or to enforce the performance of any provision of the
Notes or the Indenture.


 


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The
Trustee may maintain a proceeding even if it does not possess any of the Notes
or does not produce any of them in the proceeding.  A delay or omission by the Trustee or any
Holder of a Note in exercising any right or remedy accruing upon an Event of
Default shall not impair the right or remedy or constitute a waiver of or
acquiescence in the Event of Default. 
All remedies are cumulative to the extent permitted by law.


 


Section 7.04           Waiver of Past Defaults.


 


Holders
of not less than a majority in aggregate principal amount of the then
outstanding Notes by notice to the Trustee may on behalf of the Holders of all
of the Notes waive an existing Default or Event of Default and its consequences
hereunder, except a continuing Default or Event of Default in the payment of
the principal of, premium and/or interest on, the Notes (including in
connection with an offer to purchase) (provided, however, that the Holders of a
majority in aggregate principal amount of the then outstanding Notes may
rescind an acceleration and its consequences, including any related payment
default that resulted from such acceleration). 
Upon any such waiver, such Default shall cease to exist, and any Event
of Default arising therefrom shall be deemed to have been cured for every
purpose of the Indenture; but no such waiver shall extend to any subsequent or
other Default or impair any right consequent thereon.


 


Section 7.05           Control by Majority.


 


Holders
of a majority in aggregate principal amount of the then outstanding Notes may
direct the time, method and place of conducting any proceeding for exercising
any remedy available to the Trustee or exercising any trust or power conferred
on it.  However, the Trustee may refuse
to follow any direction that conflicts with law or the Indenture or that the
Trustee determines may be unduly prejudicial to the rights of other Holders of
Notes (it being understood that the Trustee has no affirmative duty to
determine whether or not such direction is unduly prejudicial to such Holders)
or that may involve the Trustee in personal liability.


 


Section 7.06           Limitation on Suits.


 


A
Holder of a Note may pursue a remedy with respect to the Indenture or the Notes
only if:


 


(a)           the
Holder of a Note gives to the Trustee written notice of a continuing Event of
Default;


 


(b)           the
Holders of at least 25% in principal amount of the then outstanding Notes make
a written request to the Trustee to pursue the remedy;


 


(c)           such
Holder of a Note or Holders of Notes offer and, if requested, provide to the
Trustee indemnity or security satisfactory to the Trustee against any loss,
liability or expense;


 


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(d)           the
Trustee does not comply with the request within 60 days after receipt of the
request and the offer and, if requested, the provision of indemnity; and


 


(e)           during
such 60-day period the Holders of a majority in principal amount of the then
outstanding Notes do not give the Trustee a direction inconsistent with the
request.


 


A
Holder of a Note may not use the Indenture to prejudice the rights of another
Holder of a Note or to obtain a preference or priority over another Holder of a
Note.


 


Section 7.07           Rights of Holders of Notes
to Receive Payment.


 


Notwithstanding
any other provision of the Indenture, the right of any Holder of a Note to
receive payment of principal, premium and interest on the Note, on or after the
respective due dates expressed in the Note (including in connection with an
offer to purchase), or to bring suit for the enforcement of any such payment on
or after such respective dates, shall not be impaired or affected without the
consent of such Holder.


 


Section 7.08           Collection Suit by
Trustee.


 


If
an Event of Default specified in Section 7.01(a) or (b) occurs
and is continuing, the Trustee is authorized to recover a judgment in its own
name and as trustee of an express trust against the Issuers for the whole
amount of principal of, premium and interest remaining unpaid on the Notes and
interest on overdue principal and, to the extent lawful, interest and such
further amount as shall be sufficient to cover the costs and expenses of
collection, including the reasonable compensation, expenses, disbursements and
advances of the Trustee, its agents and counsel.


 


Section 7.09           Trustee May File
Proofs of Claim.


 


The
Trustee is authorized to file such proofs of claim and other papers or
documents as may be necessary or advisable in order to have the claims of the
Trustee (including any claim for the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel) and the
Holders of the Notes allowed in any judicial proceedings relative to an Issuer
or any of the Subsidiary Guarantors (or any other obligor upon the Notes), its
creditors or its property and shall be entitled and empowered to collect,
receive and distribute any money or other property payable or deliverable on
any such claims and any custodian in any such judicial proceeding is hereby
authorized by each Holder to make such payments to the Trustee, and in the
event that the Trustee shall consent to the making of such payments directly to
the Holders, to pay to the Trustee any amount due to it for the reasonable
compensation, expenses, disbursements and advances of the Trustee, its agents
and counsel, and any other amounts due the Trustee under Section 8.07
hereof.  To the extent that the payment
of any such compensation, expenses, disbursements and advances of the Trustee,
its agents and counsel, and any other amounts due the Trustee under Section 8.07
hereof out of the estate in any such proceeding, shall be denied for any
reason, payment of the same shall be secured by a Lien on, and shall be paid
out of, any and all distributions, dividends, money, securities and other
properties that the Holders may be entitled to receive in such proceeding
whether in liquidation or under any plan of


 


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reorganization
or arrangement or otherwise.  Nothing
herein contained shall be deemed to authorize the Trustee to authorize or
consent to or accept or adopt on behalf of any Holder any plan of
reorganization, arrangement, adjustment or composition affecting the Notes or
the rights of any Holder, or to authorize the Trustee to vote in respect of the
claim of any Holder in any such proceeding.


 


Section 7.10           Priorities.


 


If
the Trustee collects any money pursuant to this Article, it shall pay out the
money in the following order:


 


First:
to the Trustee, its agents and attorneys for amounts due under Section 8.07
hereof, including payment of all compensation, expense and liabilities
incurred, and all advances made, by the Trustee and the costs and expenses of
collection;


 


Second:
to Holders of Notes for amounts due and unpaid on the Notes for principal,
premium and interest, ratably, without preference or priority of any kind,
according to the amounts due and payable on the Notes for principal, premium
and interest, respectively; and


 


Third:
to the Issuers or the Subsidiary Guarantors or to such other party as a court
of competent jurisdiction shall direct.


 


The
Trustee may fix a record date and payment date for any payment to Holders of
Notes pursuant to this Section 7.10.


 


Section 7.11           Undertaking for Costs.


 


In
any suit for the enforcement of any right or remedy under the Indenture or in
any suit against the Trustee for any action taken or omitted by it as a
Trustee, a court in its discretion may require the filing by any party litigant
in the suit of an undertaking to pay the costs of the suit, and the court in
its discretion may assess reasonable costs, including reasonable attorneys’
fees and expenses against any party litigant in the suit, having due regard to
the merits and good faith of the claims or defenses made by the party
litigant.  This Section 7.11 does
not apply to a suit by the Trustee, a suit by a Holder of a Note pursuant to Section 7.07
hereof, or a suit by Holders of more than 10% in principal amount of the then
outstanding Notes.


 


ARTICLE VIII

TRUSTEE


 


Section 8.01           Duties of Trustee.


 


(a)           If
an Event of Default has occurred and is continuing, the Trustee shall exercise
such of the rights and powers vested in it by the Indenture, and use the same
degree of care and skill in its exercise that a prudent man would exercise or
use under the circumstances in the conduct of his own affairs.


 


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(b)           Except
during the continuance of an Event of Default:


 


(i)            the duties of the Trustee shall be determined solely by
the express provisions of the Indenture and the Trustee need perform only those
duties that are specifically set forth in the Indenture and no others, and no
implied covenants or obligations shall be read into the Indenture against the
Trustee; and


 


(ii)           in the absence of bad faith on its part, the Trustee may
conclusively rely, as to the truth of the statements and the correctness of the
opinions expressed therein, upon certificates or opinions furnished to the
Trustee and conforming to the requirements of the Indenture.  However, in the case of any such certificates
or opinions which by any provision hereof are specifically required to be
furnished to the Trustee, the Trustee shall be under a duty to examine the same
to determine whether or not they conform to the requirements of the Indenture
(but need not confirm or investigate the accuracy of mathematical calculations
or other facts stated therein).


 


(c)           The
Trustee may not be relieved from liabilities for its own negligent action, its
own negligent failure to act, or its own willful misconduct, except that:


 


(i)            this paragraph does not limit the effect of paragraph (b) of
this Section;


 


(ii)           the Trustee shall not be liable for any error of judgment
made in good faith by a Responsible Officer, unless it is proved that the
Trustee was negligent in ascertaining the pertinent facts; and


 


(iii)          the Trustee shall not be liable with respect to any action
it takes or omits to take in good faith in accordance with a direction received
by it pursuant to any provision of the Indenture relating to the time, method
and place of conducting any proceeding or remedy available to the Trustee, or
exercising any trust or power conferred upon the Trustee under the Indenture.


 


(d)           Whether
or not therein expressly so provided, every provision of the Indenture that in
any way relates to the Trustee is subject to paragraphs (a), (b), and (c) of
this Section.


 


(e)           No
provision of the Indenture shall require the Trustee to expend or risk its own
funds or otherwise incur any financial liability.  The Trustee shall be under no obligation to
exercise any of its rights and powers under the Indenture at the request of any
Holders, unless such Holder shall have offered to the Trustee security or
indemnity satisfactory to it against any claim, loss, liability or expense.


 


(f)            The
Trustee shall not be liable for interest on any money received by it except as
the Trustee may agree in writing with the Partnership or MarkWest Finance.  Money


 


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held
in trust by the Trustee need not be segregated from other funds except to the
extent required by law.


 


Section 8.02           Rights of Trustee.


 


(a)           Subject
to the provisions of Section 8.01(a) hereof, the Trustee may
conclusively rely upon any document believed by it to be genuine and to have
been signed or presented by the proper Person. 
The Trustee need not investigate any fact or matter stated in the
document, but may accept the same as conclusive evidence of the truth and accuracy
of such statement or the correctness of such opinion.


 


(b)           Before
the Trustee acts or refrains from acting in the administration of the
Indenture, it may require an Officers’ Certificate or an Opinion of Counsel or
both.  The Trustee shall not be liable
for any action it takes or omits to take in good faith in reliance on such
Officers’ Certificate or Opinion of Counsel. 
The Trustee may consult with counsel of its selection and the advice of
such counsel or any Opinion of Counsel shall be full and complete authorization
and protection from liability in respect of any action taken, suffered or
omitted by it hereunder in good faith and in reliance thereon.


 


(c)           The
Trustee may execute any of its trusts or powers or perform any duties under the
Indenture either directly by or through agents or attorneys, and may in all
cases pay, subject to reimbursement as provided herein, such reasonable
compensation as it deems proper to all such agents and attorneys employed or
retained by it, and the Trustee shall not be responsible for any misconduct or negligence
of any agent or attorney appointed with due care.


 


(d)           The
Trustee shall not be liable for any action it takes or omits to take in good
faith that it believes to be authorized or within the rights or powers
conferred upon it by the Indenture.


 


(e)           Unless
otherwise specifically provided in the Indenture, any demand, request,
direction or notice from an Issuer or any Subsidiary Guarantor shall be
sufficient if signed by an Officer of the General Partner (in the case of the
Partnership),  by an Officer of MarkWest
Finance (in the case of MarkWest Finance) or 
by an Officer of such Subsidiary Guarantor (in the case of such
Subsidiary Guarantor).


 


(f)            The
Trustee shall be under no obligation to exercise any of the rights or powers
vested in it by the Indenture at the request or direction of any of the Holders
unless such Holders shall have offered to the Trustee security or indemnity
satisfactory to the Trustee against the claims, costs, expenses and liabilities
that might be incurred by it in compliance with such request or direction.


 


(g)           The
Trustee is not required to make any inquiry or investigation into facts or
matters stated in any document but the Trustee, in its discretion, may make
such further inquiry or investigation into such facts or matters as it may see
fit and, if the Trustee determines to make such further inquiry or
investigation, it shall be entitled to examine the books, records and premises
of the Issuers, personally or by agent or attorney at the sole cost of the
Issuers and


 


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shall
incur no liability or additional liability of any kind by reason of such
inquiry or investigation.


 


(h)           The
Trustee is not required to take notice or shall not be deemed to have notice of
any Default or Event of Default hereunder except Defaults or Events of Default
under Sections 7.01(a) and 7.01(b) hereof, unless a Responsible
Officer of the Trustee has actual knowledge thereof or has received notice in
writing of such Default or Event of Default from the Issuers or the Holders of
at least 25% in aggregate principal amount of the Notes then outstanding and
such notice references the Notes and this Supplemental Indenture, and in the
absence of any such notice, the Trustee may conclusively assume that no such
Default or Event of Default exists.


 


(i)            The
Trustee is not required to give any bond or surety with respect to the
performance of its duties or the exercise of its powers under the Indenture.


 


(j)            Under
no circumstances shall the Trustee be liable in its individual capacity for the
obligations evidenced by the Notes.


 


(k)           In
the event the Trustee receives inconsistent or conflicting requests and
indemnity from two or more groups of Holders of Notes, each representing less
than the aggregate principal amount of Notes outstanding required to take any
action hereunder, the Trustee, in its sole discretion may determine what
action, if any, shall be taken.


 


(l)            The
Trustee’s immunities and protections from liability and its right to
indemnification in connection with the performance of its duties under the
Indenture shall extend to the Trustee’s officers, directors, agents, attorneys
and employees.  Such immunities and
protections and right to indemnification, together with the Trustee’s right to
compensation, shall survive the Trustee’s resignation of removal, the discharge
of the Indenture and final payments of the Notes.


 


(m)          The
permissive right of the Trustee to take actions permitted by the Indenture
shall not be construed as an obligation or duty to do so.


 


(n)           Except
for information provided by the Trustee concerning the Trustee, the Trustee
shall have no responsibility for any information and any offering memorandum,
disclosure material or prospectus distributed with respect to the Notes.


 


(o)           The
Trustee shall not be liable for any action taken or omitted by it in good faith
at the direction of the Holders of not less than a majority in aggregate
principal amount of the Notes as to the time, method, and place of conducting
any proceedings for any remedy available to the Trustee or the exercising of
any power conferred by the Indenture.


 


(p)           Subject
to Section 8.01(d), whether or not therein expressly so provided, every
provision of the Indenture relating to the conduct of, or affecting the
liability of, or affording protection to the Trustee shall be subject to the
provisions of this Section 8.02.


 


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(q)           Any
action taken, or omitted to be taken, by the Trustee in good faith, pursuant to
the Indenture upon the request or authority or consent of any Person who, at
the time of making such request or giving such authority or consent, is the
Holder of any Note shall be conclusive and binding upon all future Holders of
that Note and upon securities executed and delivered in exchange therefore or
in place thereof.


 


(r)            In
no event shall the Trustee be responsible or liable for special, indirect,
punitive or consequential loss or damage of any kind whatsoever (including, but
not limited to, loss of profit) irrespective of whether the Trustee has been
advised of the likelihood of such loss or damage and regardless of the form of
action.


 


Section 8.03           Individual Rights of
Trustee.


 


The
Trustee in its commercial banking or any other capacity may become the owner or
pledgee of Notes and may otherwise deal with the Issuers, any Subsidiary
Guarantors or any Affiliate of the Partnership with the same rights it would
have if it were not Trustee.  Any
Affiliate of the Trustee or Agent may do the same with like rights and duties.  However, in the event that the Trustee
acquires any conflicting interest (as defined in the TIA) after a Default has
occurred and is continuing it must eliminate such conflict within 90 days,
apply to the SEC for permission to continue as trustee or resign.  The Trustee is also subject to Sections 8.10
and 8.11 hereof.


 


Section 8.04           Trustee’s Disclaimer.


 


The
Trustee shall not be responsible for and makes no representation as to the
validity or adequacy of the Indenture, the Notes or the Guarantees, it shall
not be accountable for the Issuers’ use of the proceeds from the Notes or any
money paid to an Issuer or upon an Issuer’s direction under any provision of
the Indenture, it shall not be responsible for the use or application of any
money received by any Paying Agent other than the Trustee, and it shall not be
responsible for any statement or recital herein or any statement in the Notes
or any other document in connection with the sale of the Notes or pursuant to
the Indenture other than its certificate of authentication.


 


Section 8.05           Notice of Defaults.


 


If
a Default or Event of Default known to the Trustee occurs, the Trustee shall
mail to Holders of Notes a notice of the Default or Event of Default within 90
days after it occurs.  Except in the case
of a Default or Event of Default in payment of principal of, premium, if any,
or interest on any Note, the Trustee may withhold the notice if and so long as
the board of directors, the executive committee or a trust committee of
directors or Responsible Officers of the Trustee in good faith determines that
withholding the notice is in the interests of the Holders of the Notes.


 


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Section 8.06           Reports by Trustee to
Holders of the Notes.


 


Within
60 days after each May 15 beginning with the May 15 following the
date of this Supplemental Indenture, and for so long as Notes remain
outstanding, the Trustee shall mail to the Holders of the Notes a brief report
dated as of such reporting date that complies with TIA Section 313(a) (but
if no event described in TIA Section 313(a) has occurred within the
twelve months preceding the reporting date, no report need be
transmitted).  The Trustee also shall
comply with TIA Section 313(b)(2). 
The Trustee shall also transmit by mail all reports as required by TIA Section 313(c).


 


A
copy of each report at the time of its mailing to the Holders of Notes shall be
mailed to the Partnership and filed with the SEC and each stock exchange on
which the Notes are listed in accordance with TIA Section 313(d).  The Issuers shall promptly notify the Trustee
when the Notes are listed on any stock exchange.


 


Section 8.07           Compensation and
Indemnity.


 


The
Issuers and the Subsidiary Guarantors shall pay to the Trustee from time to
time such compensation as shall be agreed upon in writing between the Issuers
and the Trustee for its acceptance of the Indenture and services
hereunder.  The Trustee’s compensation
shall not be limited by any law on compensation of a trustee of an express
trust.  The Issuers and the Subsidiary
Guarantors shall reimburse the Trustee promptly upon request for all reasonable
disbursements, advances and expenses incurred or made by it in addition to the
compensation for its services.  Such
expenses shall include the reasonable compensation, disbursements and expenses
of the Trustee’s agents and counsel.


 


The
Issuers and the Subsidiary Guarantors shall indemnify each of the Trustee or
any successor Trustee against any and all losses, damages, claims, liabilities
or expenses (including reasonable attorneys’ fees and expenses) incurred by it
arising out of or in connection with the acceptance or administration of its
duties under the Indenture, including the costs and expenses of enforcing the
Indenture against either of the Issuers or any Subsidiary Guarantor (including
this Section 8.07) and defending itself against any claim (whether
asserted by an Issuer, any Subsidiary Guarantor, or any Holder or any other
Person) or liability in connection with the exercise or performance of any of
its powers or duties hereunder, except to the extent any such loss, liability
or expense may be attributable to its negligence or bad faith.  The Trustee shall notify the Issuers promptly
of any claim for which it may seek indemnity. 
Failure by the Trustee to so notify the Issuers shall not relieve the
Issuers and the Subsidiary Guarantors of their obligations hereunder.  The Issuers and the Subsidiary Guarantors
shall defend the claim and the Trustee shall cooperate in the defense.  The Trustee may have separate counsel and the
Issuers and the Subsidiary Guarantors shall pay the reasonable fees and
expenses of such separate counsel; provided that the Issuers and the Subsidiary
Guarantors will not be required to pay such fees and expenses if they assume
the Trustee’s defense with counsel acceptable to and approved by the Trustee
(such approval not to be unreasonably withheld) and there is no conflict of
interest between the Issuers and the Trustee in connection with such
defense.  The Issuers and the Subsidiary
Guarantors need not pay for any settlement made without their consent, which


 


75

















 


consent
shall not be unreasonably withheld. 
Neither the Issuers nor the Subsidiary Guarantors need reimburse the
Trustee for any expense or indemnity against any liability or loss of the
Trustee to the extent such expense, liability or loss is attributable to the
negligence or bad faith of the Trustee.


 


The
obligations of the Issuers and the Subsidiary Guarantors under this Section 8.07
shall survive the satisfaction and discharge of the Indenture.


 


To
secure the Issuers’ and the Subsidiary Guarantors’ payment obligations in this
Section, the Trustee shall have a Lien (which it may exercise through right of
set-off) prior to the Notes on all money or property held or collected by the
Trustee, except that held in trust to pay principal, premium, if any, and
interest on particular Notes.  Such Lien
shall survive the satisfaction and discharge of the Indenture.  When the Trustee incurs expenses or renders
services after an Event of Default specified in Section 7.01(j) or (k) hereof
occurs, the expenses and the compensation for the services (including the fees
and expenses of its agents and counsel) are intended to constitute expenses of
administration under any Bankruptcy Law.


 


The
Trustee shall comply with the provisions of TIA Section 313(b)(2) to
the extent applicable.


 


Section 8.08           Replacement of Trustee.


 


A
resignation or removal of the Trustee and appointment of a successor Trustee
shall become effective only upon the successor Trustee’s acceptance of
appointment as provided in this Section. 
The Trustee may resign in writing at any time and be discharged from the
trust hereby created by so notifying the Issuers.  The Holders of Notes of a majority in principal
amount of the then outstanding Notes may remove the Trustee by so notifying the
Trustee and the Issuers in writing.  The
Issuers may remove the Trustee if:


 


(a)           the
Trustee fails to comply with Section 8.10 hereof;


 


(b)           the
Trustee is adjudged a bankrupt or an insolvent or an order for relief is
entered with respect to the Trustee under any Bankruptcy Law;


 


(c)           a
custodian or public officer takes charge of the Trustee or its property; or


 


(d)           the
Trustee becomes incapable of acting.


 


If
the Trustee resigns or is removed or if a vacancy exists in the office of
Trustee for any reason, the Issuers shall promptly appoint a successor
Trustee.  Within one year after the
successor Trustee takes office, the Holders of a majority in aggregate
principal amount of the then outstanding Notes may appoint a successor Trustee
to replace the successor Trustee appointed by the Issuers.


 


If
a successor Trustee does not take office within 30 days after the retiring
Trustee resigns or is removed, the retiring Trustee, the Issuers, any
Subsidiary Guarantor or the Holders


 


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of
Notes of at least 10% in aggregate principal amount of the then outstanding
Notes may petition any court of competent jurisdiction for the appointment of a
successor Trustee.


 


If
the Trustee, after written request by any Holder of a Note who has been a
Holder of a Note for at least six months, fails to comply with Section 8.10,
such Holder of a Note may petition any court of competent jurisdiction for the
removal of the Trustee and the appointment of a successor Trustee.


 


A
successor Trustee shall deliver a written acceptance of its appointment to the
retiring Trustee and to the Issuers. 
Thereupon, the resignation or removal of the retiring Trustee shall become
effective, and the successor Trustee shall have all the rights, powers and
duties of the Trustee under the Indenture. 
The successor Trustee shall mail a notice of its succession to Holders
of the Notes.  The retiring Trustee shall
promptly transfer all property held by it as Trustee to the successor Trustee,
provided all sums owing to the Trustee hereunder have been paid and subject to
the Lien provided for in Section 8.07 hereof.  Notwithstanding replacement of the Trustee
pursuant to this Section 8.08, the Issuers’ and the Subsidiary Guarantors’
obligations under Section 8.07 hereof shall continue for the benefit of
the retiring Trustee.


 


Section 8.09           Successor Trustee by
Merger, Etc.


 


If
the Trustee consolidates, merges or converts into, or transfers all or
substantially all of its corporate trust business to, another corporation or
association, the successor corporation or association without any further act
shall be the successor Trustee.  As soon
as practicable, the successor Trustee shall mail a notice of its succession to
the Issuers and the Holders of the Notes.


 


Section 8.10           Eligibility;
Disqualification.


 


There
shall at all times be a Trustee hereunder that is a corporation or association
organized and doing business under the laws of the United States of America or
of any state thereof that is authorized under such laws to exercise corporate
trust powers, that is subject to supervision or examination by federal or state
authorities and that has a combined capital and surplus of at least $50 million
as set forth in its most recent published annual report of condition.


 


The
Indenture shall always have a Trustee who satisfies the requirements of TIA Section 310(a)(1),
(2) and (5).  The Trustee is subject
to TIA Section 310(b), provided, however, that there shall be excluded
from the operation of TIA Section 310(b)(l) any indenture or
indentures under which other securities or certificates of interest or
participation in other securities of the Issuers are outstanding if the
requirements of such exclusion set forth in TIA Section 310(b)(l) are
met.  For purposes of the preceding
sentence, the optional provision permitted by the second sentence of Section 310(b)(9) of
the Trust Indenture Act shall be applicable.


 


Section 8.11           Preferential Collection of Claims Against Issuers.


 


The
Trustee is subject to TIA Section 311(a), excluding any creditor
relationship listed in TIA Section 311(b). 
A Trustee who has resigned or been removed shall be subject to TIA Section 311(a) to
the extent indicated therein.


 


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Section 8.12           U.S.A. Patriot Act.


 


The
parties hereto acknowledge that in accordance with Section 326 of the
U.S.A. Patriot Act, the Trustee, like all financial institutions and in order
to help fight the funding of terrorism and money laundering, is required to
obtain, verify, and record information that identifies each person or legal
entity that establishes a relationship or opens an account with the Trustee.
The parties to this Supplemental Indenture agree that they will provide the
Trustee with such information within their possession or control as it may
reasonably request in order for the Trustee to satisfy the requirements of the
U.S.A. Patriot Act.


 


Section 8.13           Force Majeure.


 


In
no event shall the Trustee be responsible or liable for any failure or delay in
the performance of its obligations hereunder arising out of or caused by,
directly or indirectly, forces beyond its control, including, without
limitation, strikes, work stoppages, accidents, acts of war or terrorism, civil
or military disturbances, nuclear or natural catastrophes or acts of God, and
interruptions, loss or malfunctions of utilities, communications or computer
(software and hardware) services; it being understood that the Trustee shall
use reasonable efforts which are consistent with accepted practices in the
banking industry to resume performance as soon as practicable under the
circumstances.


 


ARTICLE IX

LEGAL DEFEASANCE AND COVENANT DEFEASANCE


 


Section 9.01           Option to Effect Legal
Defeasance or Covenant Defeasance.


 


The
Issuers may, at the option of the Board of Directors of the General Partner (in
the case of the Partnership) or of the Board of Directors of MarkWest Finance
(in the case of MarkWest Finance) evidenced by a resolution set forth in an
Officers’ Certificate, at any time, elect to have either Section 9.02 or
9.03 hereof be applied to all outstanding Notes upon compliance with the
conditions set forth below in this Article IX.


 


Section 9.02           Legal Defeasance and
Discharge.


 


Upon
the Issuers’ exercise under Section 9.01 hereof of the option applicable
to this Section 9.02, the Issuers and the Subsidiary Guarantors shall,
subject to the satisfaction of the conditions set forth in Section 9.04
hereof, be deemed to have been discharged from their respective Obligations and
certain other obligations with respect to all outstanding Notes and Guarantees,
as applicable, on the date the conditions set forth below are satisfied
(hereinafter, “Legal Defeasance”).  For
this purpose, Legal Defeasance means that the Issuers and the Subsidiary
Guarantors shall be deemed to have paid and discharged the entire Indebtedness
represented by the outstanding Notes, which shall thereafter be deemed to be “outstanding”
only for the purposes of Section 9.05 hereof and the other Sections of
this Supplemental Indenture referred to in clauses (a) and (b) of
this sentence below, and to have satisfied all its other obligations under such
Notes and the Indenture (and the Trustee, on demand of and at the expense of
the Issuers, shall execute proper instruments acknowledging the same), except
for the


 


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following
provisions which shall survive until otherwise terminated or discharged
hereunder: (a) the rights of Holders of outstanding Notes to receive
solely from the trust fund described in Section 9.04 hereof, and as more
fully set forth in such Section, payments in respect of the principal of,
premium, if any, and interest on, such Notes when such payments are due, (b) the
Issuers’ obligations with respect to such Notes under Sections 3.05, 3.06,
3.07, 3.09, 3.14 and 5.02 hereof, (c) the rights, powers, trusts, duties
and immunities of the Trustee hereunder and the Issuers’ and the Subsidiary
Guarantors’ obligations in connection therewith and (d) this Article IX.  Subject to compliance with this Article IX,
the Issuers may exercise the option under this Section 9.02
notwithstanding the prior exercise of its option under Section 9.03
hereof.


 


Section 9.03           Covenant Defeasance.


 


Upon
the Issuers’ exercise under Section 9.01 hereof of the option applicable
to this Section 9.03, the Issuers and the Subsidiary Guarantors shall,
subject to the satisfaction of the conditions set forth in Section 9.04
hereof, be released from their obligations under the covenants contained in
Sections 4.09, 5.04, 5.06, 5.07, 5.08, 5.09, 5.10, 5.11, 5.12, 5.13, 5.14,
5.15, 5.16, 5.18 and 6.01(a)(iv) hereof and any covenant added to the
Indenture subsequent to the Issue Date pursuant to Section 10.01 hereof
with respect to the outstanding Notes on and after the date the conditions set
forth below are satisfied (hereinafter, “Covenant Defeasance”), and the Notes
shall thereafter be deemed not “outstanding” for the purposes of any direction,
waiver, consent or declaration or act of Holders (and the consequences of any
thereof) in connection with such covenants, but shall continue to be deemed “outstanding”
for all other purposes hereunder (it being understood that such Notes shall not
be deemed outstanding for accounting purposes). 
For this purpose, Covenant Defeasance means that, with respect to the
outstanding Notes, the Issuers may omit to comply with and shall have no
liability in respect of any term, condition or limitation set forth in any such
covenant, whether directly or indirectly, by reason of any reference elsewhere
herein to any such covenant or by reason of any reference in any such covenant
to any other provision herein or in any other document and such omission to
comply shall not constitute a Default or an Event of Default under Section 7.01
hereof, but, except as specified above, the remainder of the Indenture and such
Notes shall be unaffected thereby.  In
addition, upon the Issuers’ exercise under Section 9.01 hereof of the
option applicable to this Section 9.03 hereof, subject to the satisfaction
of the conditions set forth in Section 9.04 hereof, Sections 7.01(d) through
7.01(i) hereof shall not constitute Events of Default.


 


Section 9.04           Conditions to Legal
Defeasance or Covenant Defeasance.


 


The
following shall be the conditions to the application of either Section 9.02
or 9.03 hereof to the outstanding Notes:


 


(a)           the
Issuers must irrevocably deposit with the Trustee, in trust, for the benefit of
the Holders, cash in United States dollars, U.S. Government Obligations, or a
combination thereof, in such amounts as shall be sufficient, in the opinion of
a nationally recognized firm of independent public accountants, to pay the
principal of, premium, if any, and interest, on the outstanding Notes at the
Stated Maturity thereof or on the applicable redemption


 


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date,
as the case may be, and the Issuers must specify whether the Notes are being
defeased to Stated Maturity or to a particular redemption date;


 


(b)           in
the case of an election under Section 9.02 hereof, the Issuers shall have
delivered to the Trustee an Opinion of Counsel reasonably acceptable to the
Trustee confirming that (i) the Partnership has received from, or there
has been published by, the Internal Revenue Service a ruling or (ii) since
the Issue Date, there has been a change in the applicable federal income tax
law, in either case to the effect that, and based thereon such Opinion of
Counsel shall confirm that, the Holders of the outstanding Notes will not
recognize income, gain or loss for federal income tax purposes as a result of
such Legal Defeasance and will be subject to federal income tax on the same
amounts, in the same manner and at the same times as would have been the case
if such Legal Defeasance had not occurred;


 


(c)           in
the case of an election under Section 9.03 hereof, the Issuers shall have
delivered to the Trustee an Opinion of Counsel reasonably acceptable to the
Trustee confirming that the Holders of the outstanding Notes will not recognize
income, gain or loss for federal income tax purposes as a result of such
Covenant Defeasance and will be subject to federal income tax on the same
amounts, in the same manner and at the same times as would have been the case
if such Covenant Defeasance had not occurred;


 


(d)           no
Default or Event of Default shall have occurred and be continuing either on the
date of such deposit (other than a Default or Event of Default resulting from
the incurrence of Indebtedness all or a portion of the proceeds of which shall
be applied to such deposit);


 


(e)           such
Legal Defeasance or Covenant Defeasance shall not result in a breach or
violation of, or constitute a default under, any material agreement or
instrument (other than the Indenture) to which the Partnership or any of its
Subsidiaries is a party or by which the Partnership or any of its Subsidiaries
is bound;


 


(f)            the
Issuers shall have delivered to the Trustee an Officers’ Certificate stating
that the deposit was not made by the Issuers with the intent of preferring the
Holders over any other creditors of the Issuers or the Subsidiary Guarantors or
with the intent of defeating, hindering, delaying or defrauding other creditors
of the Issuers; and


 


(g)           the
Issuers shall have delivered to the Trustee an Officers’ Certificate and an
Opinion of Counsel, each stating that all conditions precedent provided for or
relating to the Legal Defeasance or the Covenant Defeasance have been complied
with.


 


Section 9.05           Deposited Money and
Government Securities to be Held in Trust, Other Miscellaneous Provisions.


 


Subject
to Section 12.03 hereof, all money and U.S. Government Obligations
(including the proceeds thereof) deposited with the Trustee (or other
qualifying trustee, collectively for purposes of this Section 9.05, the “Trustee”)
pursuant to Section 9.04 hereof in respect of the outstanding Notes shall
be held in trust and applied by the Trustee, in accordance with the


 


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provisions
of such Notes and the Indenture, to the payment, either directly or through any
Paying Agent (including either Issuer acting as a Paying Agent) as the Trustee
may determine, to the Holders of such Notes of all sums due and to become due
thereon in respect of principal, premium, if any, and interest, but such money
need not be segregated from other funds except to the extent required by law.


 


The
Issuers and the Subsidiary Guarantors shall pay and indemnify the Trustee
against any tax, fee or other charge imposed on or assessed against the cash or
non-callable U.S. Government Obligations deposited pursuant to Section 9.04
hereof or the principal and interest received in respect thereof other than any
such tax, fee or other charge which by law is for the account of the Holders of
the outstanding Notes.


 


Anything
in this Article IX to the contrary notwithstanding, the Trustee shall
deliver or pay to the Issuers from time to time upon the request of the Issuers
any money or non-callable U.S. Government Obligations held by it as provided in
Section 9.04 hereof which, in the opinion of a nationally recognized firm
of independent public accountants expressed in a written certification thereof
delivered to the Trustee (which may be the opinion delivered under Section 9.04(a) hereof),
are in excess of the amount thereof that would then be required to be deposited
to effect an equivalent Legal Defeasance or Covenant Defeasance.


 


If
the Issuers exercise either their Legal Defeasance or Covenant Defeasance
option, each Subsidiary Guarantor shall be released and relieved of any
obligations under its Guarantee and any security for the Notes (other than the
trust fund described in Section 9.04 hereof) shall be released.


 


Section 9.06           Reinstatement.


 


If
the Trustee or Paying Agent is unable to apply any United States dollars or
U.S. Government Obligations in accordance with Section 9.02 or 9.03
hereof, as the case may be, by reason of any legal proceeding or by reason of
any order or judgment of any court or governmental authority enjoining,
restraining or otherwise prohibiting such application, then the Issuers’ and
the Subsidiary Guarantors’ Obligations under the Indenture, the Notes and the
Guarantees, as applicable, shall be revived and reinstated as though no deposit
had occurred pursuant to Section 9.02 or 9.03 hereof until such time as
the Trustee or Paying Agent is permitted to apply all such money or U.S.
Government Obligations in accordance with Section 9.02 or 9.03 hereof, as
the case may be; provided, however, that, if the Issuers or the Subsidiary
Guarantors make any payment of principal of, premium, if any, or interest on
any Note following the reinstatement of its Obligations, the Issuers and the
Subsidiary Guarantors shall be subrogated to the rights of the Holders of such
Notes to receive such payment from the money or U.S. Government Obligations
held by the Trustee or Paying Agent.


 


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ARTICLE X

AMENDMENT, SUPPLEMENT AND WAIVER


 


Section 10.01         Without Consent of Holders
of Notes.


 


Notwithstanding
Section 10.02 of this Supplemental Indenture, the Issuers and the
Subsidiary Guarantors and the Trustee may amend or supplement the Indenture,
the Guarantees, or the Notes without the consent of any Holder of a Note:


 


(a)           to
cure any ambiguity, defect or inconsistency;


 


(b)           to
provide for uncertificated Notes in addition to or in place of Certificated
Notes;


 


(c)           to
provide for the assumption of an Issuer’s or a Subsidiary Guarantor’s
obligations to the Holders of the Notes in the case of a merger or
consolidation or sale of all or substantially all of such Issuer’s or
Subsidiary Guarantor’s properties or assets pursuant to Article VI hereof;


 


(d)           to
add or release Subsidiary Guarantors pursuant to the terms of the Indenture;


 


(e)           to
make any change that would provide any additional rights or benefits to the
Holders of the Notes or surrender any right or power conferred upon the Issuers
or the Subsidiary Guarantors by the Indenture that does not adversely affect
the rights hereunder of any Holder of the Notes, provided that any change to
conform the Indenture to the Prospectus shall not be deemed to adversely affect
such rights;


 


(f)            to
provide for the issuance of additional Notes in accordance with the limitations
set forth in the Indenture;


 


(g)           to
comply with requirements of the SEC in order to effect or maintain the
qualification of the Indenture under the TIA;


 


(h)           to
evidence or provide for the acceptance of appointment under the Indenture of a
successor Trustee;


 


(i)            to
add any additional Events of Default;


 


(j)            to
secure the Notes and/or the Guarantees; or


 


(k)           to
provide for the reorganization of the Partnership as any other form of entity
in accordance with Section 6.01(b).


 


Upon
the request of the Issuers accompanied by a resolution of the Board of
Directors of the General Partner (in the case of the Partnership), and of the
Board of Directors of MarkWest


 


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Finance
and each of the Subsidiary Guarantors (in the case of MarkWest Finance and the
Subsidiary Guarantors), authorizing the execution of any such amended or
supplemental indenture, and upon receipt by the Trustee of the documents
described in Section 10.06 hereof, the Trustee shall join with the Issuers
and each of the Subsidiary Guarantors in the execution of any amended or
supplemental indenture authorized or permitted by the terms of the Indenture
and to make any further appropriate agreements and stipulations that may be
therein contained, but the Trustee shall not be obligated to enter into such
amended or supplemental indenture that affects its own rights, duties or
immunities under the Indenture or otherwise.


 


Section 10.02         With Consent of Holders of
Notes.


 


Except
as provided below in this Section 10.02, the Issuers, the Subsidiary
Guarantors and the Trustee may amend or supplement the Indenture (including
Sections 4.09, 5.06 and 5.07 hereof), the Guarantees, and the Notes with the
consent of the Holders of at least a majority in principal amount of the Notes then
outstanding (including, without limitation, consents obtained in connection
with a purchase of, or tender offer or exchange offer for, the Notes), and,
subject to Sections 7.04 and 7.07 hereof, any existing Default or Event of
Default or compliance with any provision of the Indenture, the Guarantees or
the Notes may be waived with the consent of the Holders of a majority in
principal amount of the then outstanding Notes (including consents obtained in
connection with a tender offer or exchange offer for the Notes).


 


Upon
the request of the Issuers accompanied by a resolution of the Board of
Directors of the General Partner (in the case of the Partnership) and of the
Board of Directors of MarkWest Finance and each of the Subsidiary Guarantors
(in the case of MarkWest Finance and each of the Subsidiary Guarantors)
authorizing the execution of any such amended or supplemental indenture, and
upon the filing with the Trustee of evidence satisfactory to the Trustee of the
consent of the Holders of Notes as aforesaid, and upon receipt by the Trustee
of the documents described in Section 10.06 hereof, the Trustee shall join
with the Issuers and each of the Subsidiary Guarantors in the execution of such
amended or supplemental indenture unless such amended or supplemental indenture
affects the Trustee’s own rights, duties or immunities under the Indenture or
otherwise, in which case the Trustee may in its discretion, but shall not be
obligated to, enter into such amended or supplemental indenture.


 


It
shall not be necessary for the consent of the Holders of Notes under this Section 10.02
to approve the particular form of any proposed amendment, supplement or waiver,
but it shall be sufficient if such consent approves the substance thereof.


 


After
an amendment, supplement or waiver under this Section becomes effective,
the Issuers shall mail to the Holders of Notes affected thereby a notice
briefly describing the amendment, supplement or waiver.  Any failure of the Issuers to mail such
notice, or any defect therein, shall not, however, in any way impair or affect
the validity of any such amended or supplemental indenture or waiver.  Subject to Sections 7.04 and 7.07 hereof, the
Holders of a majority in aggregate principal amount of the Notes then
outstanding may waive compliance in a particular instance by the Issuers with
any provision of the Indenture or the Notes. 
However,


 


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without
the consent of each Holder affected, an amendment, supplement or waiver may not
(with respect to any Notes held by a non-consenting Holder):


 


(a)           reduce
the principal amount of Notes whose Holders must consent to an amendment,
supplement or waiver;


 


(b)           reduce
the principal of or change the fixed maturity of any Note or alter or waive any
of the provisions with respect to the redemption or repurchase of the Notes,
except as provided above with respect to Sections 4.09, 5.06 and 5.07 hereof;


 


(c)           reduce
the rate of or change the time for payment of interest, including default
interest, on any Note;


 


(d)           waive
a Default or Event of Default in the payment of principal of or premium, if
any, or interest on the Notes (except a rescission of acceleration of the Notes
by the Holders of at least a majority in principal amount of the then
outstanding Notes and a waiver of the payment default that resulted from such
acceleration);


 


(e)           make
any Note payable in money other than that stated in the Notes;


 


(f)            make
any change in the provisions of the Indenture relating to waivers of past
Defaults or the rights of Holders of Notes to receive payments of principal of
or premium, if any, or interest on the Notes (other than as permitted by clause
(g) below);


 


(g)           waive
a redemption or repurchase payment with respect to any Note (other than a
payment required by the covenants contained in Sections 4.09, 5.06 and 5.07
hereof);


 


(h)           except
as otherwise permitted by the Indenture, release any Subsidiary Guarantor from
any of its Obligations under its Guarantee or the Indenture, or change any
Guarantee in any manner that would adversely affect the right of Holders; or


 


(i)            make
any change in Section 7.04 or 7.07 hereof or in the foregoing amendment,
supplement and waiver provisions (except to increase any percentage set forth
therein).


 


Section 10.03         Compliance with Trust
Indenture Act.


 


Every
amendment or supplement to the Indenture, the Guarantees, or the Notes shall be
set forth in an amended or supplemental Indenture that complies with the TIA as
then in effect.


 


Section 10.04         Revocation and Effect of
Consents.


 


Until
an amendment, supplement or waiver becomes effective, a consent to it by a
Holder of a Note is a continuing consent by the Holder of a Note and every
subsequent Holder of a Note or portion of a Note that evidences the same debt
as the consenting Holder’s Note, even if notation of the consent is not made on
any Note.  However, any such Holder of a
Note or


 


84
















 


subsequent
Holder of a Note may revoke the consent as to its Note if the Trustee receives
written notice of revocation before the date the waiver, supplement or
amendment becomes effective.  An
amendment, supplement or waiver becomes effective in accordance with its terms
and thereafter binds every Holder.


 


The
Issuers may, but shall not be obligated to, fix a record date for the purpose
of determining the Holders entitled to consent to any amendment, supplement or
waiver.  If a record date is fixed, then notwithstanding
the last sentence of the immediately preceding paragraph, those Persons who
were Holders at such record date (or their duly designated proxies), and only
those Persons, shall be entitled to consent to such amendment, supplement or
waiver or revoke any consent previously given, whether or not such Persons
continue to be Holders after such record date. 
No consent shall be valid or effective for more than 90 days after such
record date except to the extent that the requisite number of consents to the
amendment, supplement or waiver have been obtained within such 90-day period or
as set forth in the next paragraph of this Section 10.04.


 


After
an amendment, supplement or waiver becomes effective, it shall bind every
Holder, unless it makes a change described in any of clauses (a) through (i) of
Section 10.02, in which case, the amendment, supplement or waiver shall
bind only each Holder of a Note who has consented to it and every subsequent
Holder of a Note or portion of a Note that evidences the same indebtedness as
the consenting Holder’s Note.


 


Section 10.05         Notation or Exchange of
Notes.


 


The
Trustee may place an appropriate notation about an amendment, supplement or
waiver on any Note thereafter authenticated. 
The Issuers in exchange for all Notes may issue and the Trustee, upon
receipt of an Issuer Order, shall authenticate new Notes (accompanied by a
notation of the Guarantees duly endorsed by the Subsidiary Guarantors) that
reflect the amendment, supplement or waiver. 
Failure to make the appropriate notation or issue a new Note shall not
affect the validity and effect of such amendment, supplement or waiver.


 


Section 10.06         Trustee to Sign Amendments, Etc.


 


The
Trustee shall sign any amended or supplemental indenture authorized pursuant to
this Article X if the amendment or supplement does not adversely affect
the rights, duties, liabilities or immunities of the Trustee.  In executing any amended or supplemental
indenture, the Trustee shall be entitled to receive and (subject to Section 8.01)
shall be fully protected in relying upon, an Officers’ Certificate of the
Partnership and an Opinion of Counsel stating that the execution of such
amended or supplemental indenture is authorized or permitted by the Indenture
and that all conditions precedent have been satisfied.


 


Section 10.07         Effect of Supplemental
Indentures.


 


Upon
the execution of any supplemental indenture under this Article X, the
Indenture shall be modified in accordance therewith, and such supplemental
indenture shall form a part of the Indenture for all purposes; and every Holder
of Notes theretofore or thereafter authenticated


 


85

















 


and
delivered hereunder shall be bound thereby. 
After a supplemental indenture becomes effective, the Issuers shall mail
to Holders a notice briefly describing such amendment.  The failure to give such notice to all
Holders, or any defect therein, shall not impair or affect the validity of an
amendment under this Section.


 


ARTICLE XI

GUARANTEES


 


Section 11.01         Guarantees.


 


Subject
to the provisions of this Article XI, each of the Subsidiary Guarantors
hereby, jointly and severally, unconditionally guarantees to each Holder of a
Note authenticated and delivered by the Trustee and to the Trustee and its successors
and assigns, irrespective of the validity and enforceability of the Indenture,
the Notes or the other Obligations of the Issuers hereunder or thereunder,
that: (a) the principal of, premium and interest on the Notes shall be
promptly paid in full when due, whether at the maturity or interest payment or
mandatory redemption date, by acceleration, redemption or otherwise, and
interest on the overdue principal of, premium and interest on the Notes, if
any, to the extent lawful, and all other Obligations of the Issuers to the
Holders or the Trustee under the Indenture and the Notes shall be promptly paid
in full or performed, all in accordance with the terms of the Indenture and the
Notes; and (b) in case of any extension of time of payment or renewal of
any Notes or any of such other Obligations, that same shall be promptly paid in
full when due or performed in accordance with the terms of the extension or
renewal, subject to any applicable grace period, whether at Stated Maturity, by
acceleration or otherwise.  Failing
payment when so due of any amount so guaranteed or any performance so
guaranteed for whatever reason, the Subsidiary Guarantors shall be jointly and
severally obligated to pay the same immediately.  The Subsidiary Guarantors hereby agree that
to the fullest extent permitted by applicable law, their obligations hereunder
shall be unconditional, irrespective of the validity, regularity or
enforceability of the Notes or the Indenture, the absence of any action to
enforce the same, any waiver or consent by any Holder of the Notes with respect
to any provisions of the Indenture and the Notes, the recovery of any judgment
against the Issuers, any action to enforce the same or any other circumstance
(other than complete performance) which might otherwise constitute a legal or
equitable discharge or defense of a Subsidiary Guarantor.  To the fullest extent permitted by applicable
law, each Subsidiary Guarantor hereby waives diligence, presentment, demand of
payment, filing of claims with a court in the event of insolvency or bankruptcy
of the Issuers, any right to require a proceeding first against the Issuers,
protest, notice and all demands whatsoever and covenants that its Guarantee
shall not be discharged except by complete performance of the obligations
contained in the Notes and the Indenture.


 


If
any Holder or the Trustee is required by any court or otherwise to return to
the Issuers or Subsidiary Guarantors, or any custodian, trustee, liquidator or
other similar official acting in relation to either the Issuers or Subsidiary
Guarantors, any amount paid by any of them to the Trustee or such Holder, these
Guarantees, to the extent theretofore discharged, shall be reinstated in full
force and effect.  Each Subsidiary
Guarantor agrees that it shall not be entitled to any right


 


86

















 


of
subrogation in relation to the Holders in respect of any Obligations guaranteed
hereby until payment in full of all Obligations guaranteed hereby.


 


Each
Subsidiary Guarantor further agrees that, as between the Subsidiary Guarantors,
on the one hand, and the Holders and the Trustee, on the other hand, (x) the
maturity of the Obligations guaranteed hereby may be accelerated as provided in
Article VII hereof for the purposes of these Guarantees, notwithstanding
any stay, injunction or other prohibition preventing such acceleration in
respect of the Obligations guaranteed hereby, and (y) in the event of any
declaration of acceleration of such Obligations as provided in Article VII
hereof, such Obligations (whether or not due and payable) shall forthwith
become due and payable by the Subsidiary Guarantors for the purpose of these
Guarantees.  The Subsidiary Guarantors
shall have the right to seek contribution from any non-paying Subsidiary
Guarantor so long as the exercise of such right does not impair the rights of
the Holders under these Guarantees.


 


Section 11.02         Limitation of Guarantor’s
Liability.


 


Each
Subsidiary Guarantor and, by its acceptance hereof, each Holder hereby confirms
that it is its intention that the Guarantee by such Subsidiary Guarantor not
constitute a fraudulent transfer or conveyance for purposes of the Bankruptcy
Law, the Uniform Fraudulent Conveyance Act, the Uniform Fraudulent Transfer Act
or any similar federal or state law to the extent applicable to the
Guarantees.  To effectuate the foregoing
intention, each such Person hereby irrevocably agrees that the Obligation of
such Subsidiary Guarantor under its Guarantee under this Article XI shall
be limited to the maximum amount as shall, after giving effect to such maximum
amount and all other (contingent or otherwise) liabilities of such Subsidiary
Guarantor that are relevant under such laws, and after giving effect to any
rights to contribution of such Subsidiary Guarantor pursuant to any agreement
providing for an equitable contribution among such Subsidiary Guarantor and
other Affiliates of the Issuers of payments made by guarantees by such parties,
result in the Obligations of such Subsidiary Guarantor in respect of such
maximum amount not constituting a fraudulent conveyance.  Each Holder, by accepting the benefits
hereof, confirms its intention that, in the event of bankruptcy, reorganization
or other similar proceeding of either of the Issuers or any Subsidiary
Guarantor in which concurrent claims are made upon such Subsidiary Guarantor
hereunder, to the extent such claims shall not be fully satisfied, each such
claimant with a valid claim against such Issuer shall be entitled to a ratable
share of all payments by such Subsidiary Guarantor in respect of such
concurrent claims.


 


Section 11.03         Execution and Delivery of
Notations of Guarantees.


 


To
evidence the Guarantees set forth in Section 11.01 hereof, each Subsidiary
Guarantor hereby agrees that a notation of the Guarantees substantially in the
form of Exhibit B shall be endorsed on each Note authenticated and
delivered by the Trustee and that the Base Indenture and Supplemental Indenture
shall each be executed on behalf of such Subsidiary Guarantor by one of its
Officers.


 


Each
Subsidiary Guarantor hereby agrees that the Guarantees set forth in Section 11.01
shall remain in full force and effect notwithstanding any failure to endorse on
each Note a


 


87

















 


notation
of the Guarantees.  If an Officer whose
signature is on the Base Indenture or Supplemental Indenture or on the notation
of Guarantees no longer holds that office at the time the Trustee authenticates
the Note on which the notation of the Guarantees is endorsed, the Guarantees
shall be valid nevertheless.


 


The
delivery of any Note by the Trustee, after the authentication thereof
hereunder, shall constitute due delivery of the Guarantees set forth in the
Indenture on behalf of the Subsidiary Guarantors.


 


Section 11.04         Releases.


 


Concurrently
with any sale of assets (including, if applicable, all of the Equity Interests
of any Subsidiary Guarantor), any Liens in favor of the Trustee in the assets
sold thereby shall be released; provided that in the event of an Asset Sale,
the Net Proceeds from such sale or other disposition are treated in accordance
with the provisions of Section 5.07 hereof.  The Guarantee and all other obligations under
the Indenture of a Subsidiary Guarantor will be released:  (i) in connection with any sale or other
disposition of all or substantially all of the assets of such Subsidiary
Guarantor (including by way of merger or consolidation) to a Person that is not
(either before or after giving effect to such transaction) a Restricted
Subsidiary, if that sale or other disposition does not violate Section 5.07
hereof; or (ii) in connection with any sale or other disposition of the
Equity Interests of a Subsidiary Guarantor to a Person that is not (either
before or after giving effect to such transaction) an Issuer or a Restricted
Subsidiary, if that sale or other disposition does not violate Section 5.07
hereof and the Subsidiary Guarantor ceases to be a Restricted Subsidiary of the
Partnership as a result of the sale or other disposition; or (iii) if the
Partnership designates any Restricted Subsidiary that is a Subsidiary Guarantor
as an Unrestricted Subsidiary; or (iv) upon Legal Defeasance or Covenant
Defeasance pursuant to Article IX hereof or upon satisfaction and
discharge of the Indenture pursuant to Article XII hereof; or (v) in
the case of any Subsidiary Guarantor other than the Operating Company, at such
time as such Subsidiary Guarantor ceases to guarantee any other Indebtedness of
either of the Issuers and any Indebtedness of the Operating Company; or (vi) in
the case of the Operating Company, at such time as the Operating Company ceases
to guarantee any other Indebtedness of either of the Issuers, provided that it
is then no longer an obligor with respect to any Indebtedness under any Credit
Facility.  Upon delivery by the
Partnership to the Trustee of an Officers’ Certificate to the effect that such
sale or other disposition was made by the Partnership in accordance with the
provisions of the Indenture, including without limitation Section 5.07
hereof, or such Guarantee is to be released pursuant to the provisions of the
immediately preceding sentence, the Trustee shall execute any documents
reasonably required in order to evidence the release of any Subsidiary
Guarantor from all of its obligations under its Guarantee and the
Indenture.  Any Subsidiary Guarantor not
released from its obligations under its Guarantee shall remain liable for the
full amount of principal of and interest on the Notes and for the other
obligations of any Subsidiary Guarantor under the Indenture as provided in this
Article XI.


 


88

















 


Section 11.05          “Trustee” to Include
Paying Agent.


 


In
case at any time any Paying Agent other than the Trustee shall have been
appointed by the Issuers and be then acting hereunder, the term “Trustee” as
used in this Article XI shall in such case (unless the context shall
otherwise require) be construed as extending to and including such Paying Agent
within its meaning as fully and for all intents and purposes as if such Paying
Agent were named in this Article XI in place of the Trustee.


 


ARTICLE XII

SATISFACTION AND DISCHARGE


 


Section 12.01         Satisfaction and
Discharge.


 


The
Indenture shall upon the request of the Issuers cease to be of further effect
(except for the Issuers’ obligations under Section 8.07 hereof, the
Issuers’ rights of optional redemption under Article IV hereof, and the
Trustee’s and the Paying Agent’s obligations under Section 12.02 and 12.03
hereof and except as provided in the penultimate paragraph of this Section 12.01)
and the Trustee, at the expense of the Issuers, shall execute proper
instruments acknowledging satisfaction and discharge of the Indenture when


 


(a)           either


 


(i)            all Notes theretofore authenticated and delivered (other
than (A) Notes which have been destroyed, lost or stolen and which have
been replaced or paid as provided in Section 3.09 and (B) Notes for
whose payment money has been deposited in trust with the Trustee or any Paying
Agent and thereafter paid to the Issuers or discharged from such trust) have
been delivered to the Trustee for cancellation; or


 


(ii)           all such Notes not theretofore delivered to the Trustee
for cancellation


 


(A)          have become due and payable;


 


(B)           shall become due and payable at their Stated Maturity
within one year by reason of the mailing of a notice of redemption or
otherwise, or


 


(C)           are to be called for redemption within one year under
arrangements satisfactory to the Trustee for the giving of notice of redemption
by the Trustee in the name, and at the expense, of the Issuers,


 


and
the Issuers or any Subsidiary Guarantor, in the case of clause (A), (B) or
(C) above, has irrevocably deposited or caused to be deposited with the
Trustee as trust funds in trust for the benefit of the Holders, cash in U.S.
dollars, U.S. Government Obligations or a combination of cash in U.S. dollars
and U.S.


 


89

















 


Government
Obligations, in amounts as will be sufficient without consideration of any
reinvestment of interest, to pay and discharge the entire indebtedness on the
Notes not delivered to the Trustee for cancellation for principal, premium, if
any, and accrued interest to the date of fixed maturity or redemption;


 


(b)           no
Default or Event of Default shall have occurred and be continuing on the date
of such deposit (other than a Default or Event of Default resulting from the
borrowing of funds to be applied to such deposit) and such deposit will not
result in a breach or violation of, or constitute a default under, any material
agreement or instrument (other than the Indenture) to which the Partnership or
any of its Subsidiaries is a party or by which the Partnership or any of its
Subsidiaries is bound;


 


(c)           the
Issuers or any Subsidiary Guarantor has paid or caused to be paid all sums then
due and payable hereunder by the Issuers;


 


(d)           the
Issuers have delivered irrevocable instructions to the Trustee to apply the
deposited money toward the payment of the Notes at fixed maturity or the redemption
date, as the case may be; and


 


(e)           the
Issuers have delivered to the Trustee an Officers’ Certificate and an Opinion
of Counsel, each stating that all conditions precedent herein provided for
relating to the satisfaction and discharge of the Indenture (“Discharge”) have
been satisfied.


 


Notwithstanding
the satisfaction and discharge of the Indenture, the Issuers’ obligations in
3.05, 3.06, 3.07, 3.09, 3.14, 5.02, 8.07, 8.08, 12.02, 12.03 and 12.04, and the
Trustee’s and Paying Agent’s obligations in Section 12.03 shall survive
until the Notes are no longer outstanding. 
Thereafter, only the Issuers’ obligations in Section 12.03 shall
survive.


 


In
order to have money available on a payment date to pay principal (and premium,
if any, on) or interest on the Notes, the U.S. Government Obligations shall be
payable as to principal (and premium, if any) or interest at least one Business
Day before such payment date in such amounts as shall provide the necessary
money.  The U.S. Government Obligations
shall not be callable at the issuer’s option.


 


Section 12.02         Application of Trust.


 


All
money deposited with the Trustee pursuant to Section 12.01 shall be held
in trust and, at the written direction of the Issuers, be invested prior to
maturity in U.S. Government Obligations, and applied by the Trustee in
accordance with the provisions of the Notes and the Indenture, to the payment,
either directly or through any Paying Agent as the Trustee may determine, to
the Persons entitled thereto, of the principal (and premium, if any) and
interest for the payment of which money has been deposited with the Trustee;
but such money need not be segregated from other funds except to the extent
required by law.


 


90

















 


Section 12.03         Repayment of the Issuers.


 


The
Trustee and the Paying Agent shall promptly pay to the Issuers upon written
request any excess money or securities held by them at any time.


 


Subject
to applicable escheat laws, the Trustee and the Paying Agent shall notify the
Issuers of, and pay to the Issuers upon written request, any money held by them
for the payment of principal or interest that remains unclaimed for two years
after the date upon which such payment shall have become due; provided that the
Issuers shall have either caused notice of such payment to be mailed to each
Holder of the Notes entitled thereto no less than 30 days prior to such
repayment or within such period shall have published such notice in a financial
newspaper of widespread circulation published in The City of New York,
including, without limitation, The Wall Street
Journal (national edition).  After payment to the Issuers, Holders
entitled to the money must look to the Issuers for payment as general creditors
unless an applicable abandoned property law designates another Person, and all
liability of the Trustee and such Paying Agent with respect to such money shall
cease.  In the absence of a written
request from the Issuers to return unclaimed funds to the Issuers, the Trustee
shall from time to time deliver all unclaimed funds to or as directed by
applicable escheat authorities, as determined by the Trustee in its sole
discretion, in accordance with the customary practices and procedures of the
Trustee.


 


Section 12.04         Reinstatement.


 


If
the Trustee or Paying Agent is unable to apply any money or U.S. Government
Obligations in accordance with Section 12.01 by reason of any legal
proceeding or by reason of any order or judgment of any court of governmental
authority enjoining, restraining or otherwise prohibiting such application, the
Issuers’ and Subsidiary Guarantors’ Obligations under the Indenture, the Notes
and the Guarantees, as applicable, shall be revived and reinstated as though no
deposit has occurred pursuant to Section 12.01 until such time as the
Trustee or Paying Agent is permitted to apply all such money or U.S. Government
Obligations in accordance with Section 12.02, provided, however, that if
the Issuers or the Subsidiary Guarantors have made any payment of interest or
premium, if any, on or principal of any Notes because of the reinstatement of
their Obligations, the Issuers or such Subsidiary Guarantors shall be
subrogated to the rights of the Holders of such Notes to receive such payment
from the money or U.S. Government Obligations held by the Trustee or Paying
Agent.


 


ARTICLE XIII

MISCELLANEOUS


 


Section 13.01         Notices.


 


Any
notice or communication by the Issuers or the Trustee to the others is duly
given if in writing (in the English language) and delivered in person or mailed
by first class mail (registered or certified, return receipt requested),
telecopier or overnight air courier guaranteeing next day delivery, to the
others’ address:


 


91

















 


If
to the Issuers or any Subsidiary Guarantor:


 


MarkWest
Energy Partners, L.P.


1515
Arapahoe St., Tower 2, Suite 700


Denver,
Colorado  80202


Attention:
Chief Financial Officer


 


With
a copy to:


 


Vinson &
Elkins L.L.P.


2300
First City Tower


1001
Fannin St.


Houston,
Texas  77002


Telecopier
No.: (713) 615-5861


Attention:
David P. Oelman, Esq.


 


If
to the Trustee or Paying Agent:


 


Wells
Fargo Bank, National Association


1445
Ross Avenue — Second Floor


Dallas,
Texas  75202-2812


Attention:  Corporate Trust Department


Telecopier
No.:  (214) 777-4086


 


The
Issuers, any Subsidiary Guarantor or the Trustee, by notice to the others may
designate additional or different addresses for subsequent notices or
communications.


 


All
notices and communications (other than those sent to Holders) shall be deemed
to have been duly given: at the time delivered by hand, if personally
delivered; five Business Days after being deposited in the mail, postage
prepaid, if mailed; when receipt is acknowledged, if sent by facsimile
transmission; and the next Business Day after timely delivery to the courier,
if sent by overnight air courier guaranteeing next day delivery.


 


Any
notice or communication to a Holder shall be mailed by first class mail,
certified or registered, return receipt requested, or by overnight air courier
guaranteeing next day delivery to its address shown on the register kept by the
Registrar.  Any notice or communication
shall also be so mailed to any Person described in TIA Section 313(c), to
the extent required by the TIA.  Failure
to mail a notice or communication to a Holder or any defect in it shall not
affect its sufficiency with respect to other Holders.


 


If
a notice or communication is mailed in the manner provided above within the
time prescribed, it is duly given, whether or not the addressee receives it.


 


If
either of the Issuers mails a notice or communication to Holders, it shall mail
a copy to the Trustee and each Agent at the same time.


 


92

















 


Section 13.02         Communication by Holders
of Notes with Other Holders of Notes.


 


The
Trustee is subject to TIA Section 312(b), and Holders may communicate
pursuant thereto with other Holders with respect to their rights under the
Indenture or the Notes.  The Issuers, the
Subsidiary Guarantors, the Trustee, the Registrar and anyone else shall have
the protection of TIA Section 312(c).


 


Section 13.03         Certificate and Opinion as
to Conditions Precedent.


 


Upon
any request or application by the Issuers or any Subsidiary Guarantor to the
Trustee to take any action under the Indenture, the Issuers or such Subsidiary
Guarantors shall furnish to the Trustee:


 


(a)           an
Officers’ Certificate in form and substance reasonably satisfactory to the
Trustee (which shall include the statements set forth in Section 13.04
hereof) stating that, in the opinion of the signers, all conditions precedent
and covenants, if any, provided for in the Indenture relating to the proposed
action have been satisfied; and


 


(b)           an
Opinion of Counsel in form and substance reasonably satisfactory to the Trustee
(which shall include the statements set forth in Section 13.04 hereof)
stating that, in the opinion of such counsel, all such conditions precedent and
covenants have been satisfied.


 


In
any case where several matters are required to be certified by, or covered by
an opinion of, any specified Person, it is not necessary that all such matters
be certified by, or covered by the opinion of, only one such Person, or that
they be so certified or covered by only one document, but one such Person may
certify or give an opinion with respect to some matters and one or more such
Persons as to other matters, and any such Person may certify or give an opinion
as to such matters in one or several documents.


 


Any
certificate or opinion of an Officer of the General Partner, an Issuer or any
Subsidiary Guarantor may be based, insofar as it relates to legal matters, upon
a certificate or opinion of, or representations by, counsel, unless such
Officer knows, or in the exercise of reasonable care should know, that the
certificate or opinion or representations with respect to the matters upon
which his certificate or opinion is based are erroneous.  Any such certificate or Opinion of Counsel
may be based, and may state that it is so based, insofar as it relates to
factual matters, upon a certificate or opinion of, or representations by, an
Officer or Officers of the General Partner, an Issuer or such Subsidiary
Guarantor stating that the information with respect to such factual matters is
in possession of the General Partner, an Issuer or such Subsidiary Guarantor,
unless such counsel knows, or in the exercise of reasonable care should know,
that the certificate of opinion or representations with respect to such matters
are erroneous.


 


Where
any Person is required to make, give or execute two or more applications,
requests, consents, certificates, statements, opinions or other instruments
under the Indenture, they may, but need not, be consolidated and form one
instrument.


 


93

















 


Section 13.04         Statements Required in
Certificate or Opinion.


 


Each
certificate or opinion with respect to compliance with a condition or covenant
provided for in the Indenture (other than a certificate provided pursuant to
TIA Section 314(a)(4)) shall comply with the provisions of TIA Section 314(e) and
shall include:


 


(a)           a
statement that the person making such certificate or opinion has read such
covenant or condition;


 


(b)           a
brief statement as to the nature and scope of the examination or investigation
upon which the statements or opinions contained in such certificate or opinion
are based;


 


(c)           a
statement that, in the opinion of such person, he or she has made such
examination or investigation as is necessary to enable him or her to express an
informed opinion as to whether or not such covenant or condition has been
satisfied; and


 


(d)           a
statement as to whether or not, in the opinion of such person, such condition
or covenant has been complied with.


 


Section 13.05         No Personal Liability of
Directors, Officers, Employees and Unitholders and No Recourse Against General
Partner.


 


No
past, present or future director, officer, partner, employee, incorporator,
manager or unitholder or other owner of Equity Interests of the Issuers, the
General Partner or any Subsidiary Guarantor, as such, shall have any liability
for any Obligations of the Issuers or the Subsidiary Guarantors under the
Notes, the Indenture or the Guarantees or for any claim based on, in respect
of, or by reason of, such Obligations or their creation.  Each Holder by accepting a Note waives and
releases all such liability.  The waiver
and release are part of the consideration for issuance of the Notes.


 


Section 13.06         No Adverse Interpretation
of Other Agreements.


 


The
Indenture may not be used to interpret any other indenture, loan or debt
agreement of either of the Issuers or any Subsidiary of the Partnership or of
any other Person.  Any such indenture,
loan or debt agreement may not be used to interpret the Indenture or the
Guarantees.


 


Section 13.07         Successors.


 


All
agreements of the Issuers and the Subsidiary Guarantors in the Indenture, the
Notes and the Guarantees shall bind their respective successors.  All agreements of the Trustee in the
Indenture shall bind its successors. Any act or proceeding pursuant to any
provision of the Indenture authorized or required to be done or performed by
any board, committee or officer of an Issuer shall and may be done and
performed with like force and effect by the like board, committee or officer of
any successor.


 


94

















 


Section 13.08         Counterpart Originals.


 


The
parties may sign any number of copies of this Supplemental Indenture, and each
party hereto may sign any number of separate copies of this Supplemental
Indenture. Each signed copy shall be an original, but all of them together
represent the same agreement. The exchange of copies of this Supplemental
Indenture and of signature pages by facsimile or PDF transmission shall
constitute effective execution and delivery of this Supplemental Indenture as
to the parties hereto and may be used in lieu of the original Supplemental
Indenture for all purposes. Signatures of the parties hereto transmitted by
facsimile or PDF shall be deemed to be their original signatures for all
purposes.


 


Section 13.09         Indenture and Notes to Be
Construed in Accordance with the Laws of the State of New York.


 


THIS
SUPPLEMENTAL INDENTURE, THE INDENTURE, EACH NOTE AND THE GUARANTEES SHALL BE
DEEMED TO BE NEW YORK CONTRACTS, AND FOR ALL PURPOSES SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF SAID STATE.


 


Section 13.10         Provisions Required by TIA
to Control.


 


If
and to the extent that any provision of the Indenture limits, qualifies or
conflicts with another provision included in the Indenture which is required to
be included in an indenture qualified under the TIA by any of Sections 310 to
318, inclusive, of the TIA, such required provision shall control.


 


Section 13.11         Rules by Trustee,
Paying Agent and Registrar.


 


The
Trustee may make reasonable rules for action by or a meeting of
Holders.  The Registrar and any Paying
Agent may make reasonable rules for their functions.


 


Section 13.12         Severability.


 


In
case any provision in the Indenture or the Notes shall be invalid, illegal or
unenforceable, the validity, legality and enforceability of the remaining
provisions shall not in any way be affected or impaired thereby.


 


Section 13.13         Table of Contents,
Headings, Etc.


 


The
Table of Contents, Cross-Reference Table and headings of the Articles and
Sections of this Supplemental Indenture have been inserted for convenience of
reference only, are not to be considered a part of the Indenture and shall in
no way modify or restrict any of the terms or provisions hereof.


 


95

















 


[Signatures
on following pages]


 


96
















 


IN
WITNESS WHEREOF, the parties have executed this Supplemental Indenture as of
the date first written above.


 


 


	
   

  	
   

  	
  MARKWEST
  ENERGY FINANCE  CORPORATION

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/
  Nancy Buese

  
	
   

  	
   

  	
   

  	
  Nancy
  Buese

  
	
   

  	
   

  	
   

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  MARKWEST
  ENERGY PARTNERS, L.P.

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/
  Nancy Buese

  
	
   

  	
   

  	
   

  	
  Nancy
  Buese

  
	
   

  	
   

  	
   

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  MARKWEST
  HYDROCARBON, INC.

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/
  Nancy Buese

  
	
   

  	
   

  	
   

  	
  Nancy
  Buese

  
	
   

  	
   

  	
   

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  MARKWEST
  ENERGY GP, L.L.C.

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/
  Nancy Buese

  
	
   

  	
   

  	
   

  	
  Nancy
  Buese

  
	
   

  	
   

  	
   

  	
  Senior
  Vice President and Chief Financial Officer

  



 


95

















 


	
   

  	
   

  	
  MASON
  PIPELINE LIMITED LIABILITY  COMPANY

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Hydrocarbon, Inc.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Sole Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/
  Nancy Buese

  
	
   

  	
   

  	
   

  	
  Nancy
  Buese

  
	
   

  	
   

  	
   

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  MARKWEST
  ENERGY OPERATING  COMPANY, L.L.C.

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/
  Nancy Buese

  
	
   

  	
   

  	
   

  	
  Nancy
  Buese

  
	
   

  	
   

  	
   

  	
  Senior
  Vice President and Chief Financial Officer

  



 


96

















 




	
   

  	
   

  	
  MARKWEST BLACKHAWK, L.L.C.

  
	
   

  	
   

  	
  MARKWEST ENERGY APPALACHIA,
  L.L.C.

  
	
   

  	
   

  	
  MARKWEST ENERGY EAST  TEXAS GAS COMPANY, L.L.C.

  
	
   

  	
   

  	
  MARKWEST GAS MARKETING, L.L.C.

  
	
   

  	
   

  	
  MARKWEST GAS SERVICES, L.L.C.

  
	
   

  	
   

  	
  MARKWEST JAVELINA COMPANY,
  L.L.C.

  
	
   

  	
   

  	
  MARKWEST JAVELINA PIPELINE
  COMPANY, L.L.C.

  
	
   

  	
   

  	
  MARKWEST LIBERTY GAS GATHERING,
  L.L.C.

  
	
   

  	
   

  	
  MARKWEST MARKETING, L.L.C.

  
	
   

  	
   

  	
  MARKWEST NEW MEXICO, L.L.C.

  
	
   

  	
   

  	
  MARKWEST PINNACLE, L.L.C.

  
	
   

  	
   

  	
  MARKWEST PIPELINE COMPANY,
  L.L.C.

  
	
   

  	
   

  	
  MARKWEST PNG UTILITY, L.L.C.

  
	
   

  	
   

  	
  MARKWEST POWER TEX, L.L.C.

  
	
   

  	
   

  	
  MARKWEST TEXAS PNG UTILITY, L.L.C.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Operating Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Sole Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/
  Nancy Buese

  
	
   

  	
   

  	
   

  	
  Nancy
  Buese

  
	
   

  	
   

  	
   

  	
  Senior
  Vice President and Chief Financial Officer

  






 


97

















 




	
   

  	
   

  	
  MARKWEST
  MICHIGAN PIPELINE COMPANY, L.L.C.

  
	
   

  	
   

  	
  MARKWEST
  OKLAHOMA GAS COMPANY, L.L.C.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Operating Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/
  Nancy Buese

  
	
   

  	
   

  	
   

  	
  Nancy
  Buese

  
	
   

  	
   

  	
   

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  MATREX,
  L.L.C.

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  West
  Shore Processing Company L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Sole Member and Manager

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Operating Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Sole Member and Manager

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/
  Nancy Buese

  






 


98

















 




	
   

  	
   

  	
   

  	
  Nancy
  Buese

  
	
   

  	
   

  	
   

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  MARKWEST MCALESTER, L.L.C.

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Oklahoma Gas Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Sole Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Operating Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:
  

  	
  /s/
  Nancy Buese

  
	
   

  	
   

  	
   

  	
  Nancy
  Buese

  
	
   

  	
   

  	
   

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  WEST
  SHORE PROCESSING COMPANY L.L.C.

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Operating Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/
  Nancy Buese

  






 


99

















 




	
   

  	
   

  	
   

  	
  Nancy
  Buese

  
	
   

  	
   

  	
   

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  WELLS
  FARGO BANK, NATIONAL  ASSOCIATION, AS TRUSTEE

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  /s/
  Patrick Giordano

  
	
   

  	
   

  	
   

  	
  Patrick
  Giordano

  
	
   

  	
   

  	
   

  	
  Vice
  President

  






 


100
















 


SCHEDULE A


 


Schedule of Subsidiary Guarantors


 


MarkWest
Energy Operating Company, L.L.C.


MarkWest
Hydrocarbon, Inc.


MarkWest
Energy GP, L.L.C.


MarkWest
Blackhawk, L.L.C.


MarkWest
Energy Appalachia, L.L.C.


MarkWest
Energy East Texas Gas Company, L.L.C.


MarkWest
Gas Services, L.L.C.


MarkWest
Javelina Company, L.L.C.


MarkWest
Javelina Pipeline Company, L.L.C.


MarkWest
Michigan Pipeline Company, L.L.C.


MarkWest
New Mexico, L.L.C.


MarkWest Pinnacle, L.L.C.


MarkWest
Pipeline Company, L.L.C.


MarkWest
PNG Utility, L.L.C.


MarkWest
Power Tex, L.L.C.


MarkWest
Texas PNG Utility, L.L.C.


MarkWest
Oklahoma Gas Company, L.L.C.


Mason
Pipeline Limited Liability Company


Matrex,
L.L.C.


MarkWest
Liberty Gas Gathering, L.L.C.


MarkWest
Marketing, L.L.C.


MarkWest
Gas Marketing, L.L.C.


MarkWest
McAlester, L.L.C.


West
Shore Processing Company, L.L.C.


 

















 


Exhibit A


FORM OF NOTE


 


(Face of Note)


 


THIS NOTE IS A GLOBAL NOTE WITHIN THE MEANING OF THE
INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITARY
OR A NOMINEE THEREOF. THIS NOTE MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR
A NOTE REGISTERED, AND NO TRANSFER OF THIS NOTE IN WHOLE OR IN PART MAY BE
REGISTERED, IN THE NAME OF ANY PERSON OTHER THAN SUCH DEPOSITARY OR A
NOMINEE THEREOF, EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE
INDENTURE.


 


UNLESS
THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY
TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), NEW YORK, NEW YORK, TO THE
ISSUERS OR THEIR AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND
ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR SUCH
OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY
PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED
BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE
HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE
REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.(1)


 


CUSIP: 570506AM7


 


63⁄4% Senior Notes due 2020


 


	
  No.      

  	
  $                        

  



 


MARKWEST ENERGY PARTNERS, L.P.

and

MARKWEST ENERGY FINANCE CORPORATION


 


promise
to pay to                              
or registered assigns, the principal sum of                                              
dollars of the United States of America [or such greater or lesser 


 






(1) 
This is included in Global Notes only.


 


Exhibit A-1

















 


amount
as may from time to time be endorsed on the Schedule of Exchanges of Interests
in the Global Note](2)  on November 1,
2020.


 


Interest
Payment Dates: May 1 and November 1 of each year


 


Record
Dates: April 15 and October 15


 


Reference
is hereby made to the further provisions of this Note set forth on the reverse
hereof, which further provisions shall for all purposes have the same effect as
if set forth at this place.


 


Unless
the certificate of authorization hereon has been duly executed by the Trustee
referred to on the reverse hereof by manual signature, this Note shall not be
entitled to any benefit of the Indenture or be valid or obligatory for any
purpose.


 


	
  MARKWEST
  ENERGY FINANCE CORPORATION

  	
   

  	
  MARKWEST
  ENERGY PARTNERS, L.P.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:
  

  	
  MarkWest
  Energy GP, L.L.C., its General Partner

  
	
   

  	
   

  	
   

  	
   

  
	
  By:
  

  	
   

  	
   

  	
  By:
  

  	
   

  
	
  Name:

  	
   

  	
   

  	
  Name:
  

  	
   

  
	
  Title:

  	
   

  	
   

  	
  Title:

  	
   

  



 


Certificate
of Authentication:


 


This
is one of the Notes referred to in the within-mentioned Indenture.


 


WELLS
FARGO BANK, NATIONAL ASSOCIATION, as Trustee


 


	
  By:

  	
   

  	
   

  
	
  Authorized Signatory

  	
   

  
	
   

  	
   

  
	
  Date
  of Authentication:                  
          ,           

  	
   

  



 






(2)  This is included in Global Notes only.


 


Exhibit A-2

















 


[Back of Note]


 


63⁄4% Senior Notes due 2020


 


Capitalized
terms used herein shall have the meanings assigned to them in the Indenture
referred to below unless otherwise indicated.


 


1.             Interest.  MarkWest Energy Partners, L.P., a Delaware
limited partnership (the “Partnership”), and MarkWest Energy Finance
Corporation, a Delaware corporation (“MarkWest Finance” and, together with the
Partnership, the “Issuers”), promise to pay interest on the principal amount of
this Note at 63⁄4% per annum.  The Issuers
will pay interest semi-annually on May 1 and November 1 of each year,
or if any such day is not a Business Day, on the next succeeding Business Day
(each an “Interest Payment Date”). 
Interest on the Notes will accrue from the most recent date to which
interest has been paid or, if no interest has been paid, from November 2,
2010; provided that if there is no existing Default in the payment of interest,
and if this Note is authenticated between a record date referred to on the face
hereof and the next succeeding Interest Payment Date, interest shall accrue
from such next succeeding Interest Payment Date; provided, further, that the
first Interest Payment Date shall be May 1, 2011.  The Issuers shall pay interest (including
post-petition interest in any proceeding under any Bankruptcy Law) on overdue
principal and premium, if any, from time to time on demand at the rate then in
effect; the Issuers shall pay interest (including post-petition interest in any
proceeding under any Bankruptcy Law) on overdue installments of interest,
without regard to any applicable grace periods, from time to time on demand at
the same rate to the extent lawful. 
Interest will be computed on the basis of a 360-day year comprised of
twelve 30-day months.


 


2.             Method of Payment.  The Issuers will pay interest on the Notes
(except defaulted interest) to the Persons who are registered Holders of Notes
at the close of business on the April 15 or October 15  next preceding the Interest Payment Date, even if such
Notes are cancelled after such record date and on or before such Interest
Payment Date, except as provided in Section 3.12 of the Indenture with
respect to defaulted interest.  The Notes
will be payable as to principal, premium and interest at the office or agency
of the Paying Agent maintained for such purpose in Dallas, Texas, or, at the
option of the Issuers, payment of interest may be made by check mailed to the
Holders at their addresses set forth in the Register, and provided that payment
by wire transfer of immediately available funds will be required with respect
to principal of, interest and premium on, all Global Notes and all other Notes
the Holders of which shall have provided wire transfer instructions to the
Issuers or the Paying Agent.  Such
payment shall be in such coin or currency of the United States of America as at
the time of payment is legal tender for payment of public and private debts.


 


3.
            Paying Agent and Registrar.  Initially, Wells Fargo Bank, National
Association, the Trustee under the Indenture, will act as Paying Agent and
Registrar.  The Issuers may change any
Paying Agent or Registrar without prior notice to any Holder.  The Issuers or any of their Subsidiaries may
act in any such capacity.


 


Exhibit A-3

















 


4.
            Indenture.  The Issuers issued the Notes under an
Indenture dated as of November 2, 2010 among the Issuers, the Subsidiary
Guarantors and the Trustee, as supplemented and amended by the First
Supplemental Indenture, dated November 2, 2010 among the Issuers, the
Subsidiary Guarantors and the Trustee. 
The terms of the Notes include those stated in the Indenture and those
made part of the Indenture by reference to the Trust Indenture Act of 1939, as
amended (15 U.S. Code Sections 77aaa-77bbbb). 
The Notes are subject to all such terms, and Holders are referred to the
Indenture and such Act for a statement of such terms.  To the extent any provision of this Note conflicts
with the express provisions of the Indenture, the provisions of the Indenture
shall govern and be controlling to the extent permitted by law.  The Notes are unsecured general obligations
of the Issuers.


 


5.
            Optional Redemption.  Subject to the additional terms and
conditions set forth in the Indenture:


 


On and after November 1, 2015, the Issuers
shall have the option to redeem the Notes, in whole or in part from time to
time, on at least 30 but not more than 60 days’ prior notice mailed to the registered
address of each Holder of Notes to be so redeemed, at the redemption prices
(expressed as percentages of principal amount) set forth below, plus accrued
and unpaid interest on the Notes, if any, to the applicable redemption date
(subject to the right of Holders of record on the relevant record date to
receive interest due on an Interest Payment Date that is on or prior to the
redemption date), if redeemed during the twelve-month period beginning on November 1
of the years indicated below:


 


	
  Year

  	
   

  	
  Percentage

  	
   

  
	
  2015

  	
   

  	
  103.375

  	
  %

  
	
  2016

  	
   

  	
  102.250

  	
  %

  
	
  2017

  	
   

  	
  101.125

  	
  %

  
	
  2018
  and thereafter

  	
   

  	
  100.000

  	
  %

  



 


(a)           Before
November 1, 2015, the Issuers may redeem all or, from time to time, a part
of the Notes upon not less than 30 nor more than 60 days’ notice, at a redemption
price equal to:


 


(i)            100% of the aggregate principal amount of the Notes to be
redeemed, plus accrued and unpaid interest, if any, to the applicable
redemption date (subject to the right of Holders of record on the relevant
record date to receive interest due on an Interest Payment Date that is on or
prior to the redemption date), plus


 


(ii)           the Make Whole Amount.


 


(b)           Before
November 1, 2013, the Issuers may on any one or more occasions redeem in
the aggregate up to 35% of the aggregate principal amount of Notes issued under
the Indenture, upon not less than 30 nor more than 60 days’ notice, with the
net cash proceeds of one or more Equity Offerings at a redemption price equal
to 106.750% of the principal amount of the Notes to be redeemed, plus accrued
and unpaid interest, if any, to the redemption date (subject to 


 


Exhibit A-4

















 


the right of Holders of record on the relevant
record date to receive interest due on an Interest Payment Date that is on or prior
to the redemption date); provided that


 


(i)            at least 65% of the aggregate principal amount of Notes
issued under the Indenture remains outstanding after each such redemption; and


 


(ii)           any redemption occurs within 60 days after the closing of
such Equity Offering (without regard to any over-allotment option).


 


(c)           In
the event that Holders of not less than 90% of the aggregate principal amount
of the outstanding Notes accept a Change of Control Offer and the Partnership
purchases all of the Notes held by such Holders, the Issuers will have the
right, upon not less than 30 nor more than 60 days’ notice, given not more than
30 days following the purchase pursuant to the Change of Control Offer
described below, to redeem all of the Notes that remain outstanding following
such purchase at a redemption price equal to the Change of Control Payment
plus, to the extent not included in the Change of Control Payment, accrued and
unpaid interest on the notes that remain outstanding, to the date of redemption
(subject to the right of holders of record on the relevant record date to
receive interest due on an Interest Payment Date that is on or prior to the
redemption date).


 


6.
            Mandatory Redemption.  Except as set forth in paragraph 7 below, the
Issuers shall not be required to make mandatory redemption or sinking fund
payments with respect to the Notes or to repurchase the Notes at the option of
the Holders.


 


7.
            Repurchase at Option of
Holder.  Subject to the additional terms
and conditions set forth in the Indenture:


 


If
there is a Change of Control, each Holder of Notes will have the right to
require the Issuers to repurchase all or any part (equal to $2,000 or an
integral multiple of $1,000 in excess thereof) of such Holder’s Notes (the “Change
of Control Offer”) at a purchase price equal to 101% of the aggregate principal
amount of the Notes repurchased plus accrued and unpaid interest thereon, if
any, to the date of purchase.  Within 30
days following any Change of Control, the Partnership shall mail a notice to
each Holder setting forth the procedures governing the Change of Control Offer
as required by the Indenture and information regarding such other matters as is
required under Section 5.06 of the Indenture.  The Holder of this Note may elect to have
this Note or a portion hereof in an authorized denomination purchased by
completing the form entitled “Option of Holder to Elect Purchase” appearing
below and tendering this Note pursuant to the Change of Control Offer.


 


If
the Issuers or any Restricted Subsidiary of the Partnership consummates an
Asset Sale, in certain circumstances specified in Section 5.07 of the
Indenture the Issuers shall commence a pro rata offer to all Holders of Notes
and all holders of other Indebtedness that is pari passu in right of payment
with the Notes containing provisions similar to those set forth in the
Indenture with respect to offers to purchase or redeem with the proceeds of
sales of assets (an “Asset Sale 


 


Exhibit A-5

















 


Offer”) pursuant to Section 4.09 of the
Indenture to purchase the maximum principal amount of Notes and such other pari
passu Indebtedness that may be purchased out of the Excess Proceeds at an offer
price in cash in an amount equal to 100% of the principal amount thereof plus
accrued and unpaid interest thereon, if any, to the date of purchase in
accordance with the procedures set forth in the Indenture.  If the aggregate principal amount of Notes
surrendered by Holders thereof exceeds the amount of Excess Proceeds allocated
for repurchase of Notes, the Trustee shall select the Notes to be purchased on
a pro rata basis.  Holders of Notes that
are the subject of an Asset Sale Offer will receive an offer to purchase from
the Issuers prior to any related purchase date and may elect to have such Notes
purchased by completing the form entitled “Option of Holder to Elect Purchase”
on the reverse of the Notes.


 


8.
            Notice of Redemption.  Notice of redemption will be mailed at least
30 days but not more than 60 days before the redemption date to each Holder
whose Notes are to be redeemed at its registered address, except that
redemption notices may be mailed more than 60 days prior to a redemption date
if the notice is issued in connection with a Legal Defeasance, Covenant Defeasance
or Discharge.  Notes in denominations
larger than $2,000 may be redeemed in part but only in whole multiples of
$1,000 unless all of the Notes held by a Holder are to be redeemed.  On and after the redemption date interest
ceases to accrue on Notes or portions thereof called for redemption unless the
Issuers defaults in making such redemption payment.


 


9.
            Denominations, Transfer,
Exchange.  The Notes are in registered
form without coupons in minimum denominations of $2,000 or integral multiples
of $1,000 in excess thereof.  The
transfer of Notes may be registered and Notes may be exchanged as provided in
the Indenture.  The Registrar and the
Trustee may require a Holder, among other things, to furnish appropriate
endorsements and transfer documents and the Issuers may require a Holder to pay
any taxes and fees required by law or permitted by the Indenture.  The Issuers need not exchange or register the
transfer of any Note or portion of a Note selected for redemption, except for
the portion of any Note being redeemed in part that is not being redeemed.  Also, the Issuers need not exchange or
register the transfer of any Notes for a period of 15 days before the mailing
of a notice of redemption or during the period between a record date and the
corresponding Interest Payment Date.


 


10.
          Persons Deemed Owners.  The registered Holder of a Note may be
treated as its owner for all purposes.


 


11.
          Amendment, Supplement and
Waiver.  Subject to certain exceptions,
the Indenture, the Guarantees or the Notes may be amended or supplemented with
the consent of the Holders of at least a majority in aggregate principal amount
of the then outstanding Notes, and any existing default or compliance with any
provision of the Indenture, the Guarantees or the Notes may be waived with the
consent of the Holders of a majority in aggregate principal amount of the then
outstanding Notes.  Without the consent
of any Holder of a Note, the Indenture, the Guarantees or the Notes may be
amended or supplemented to cure any ambiguity, defect or inconsistency, to
provide for uncertificated Notes in addition to or in place of Certificated
Notes, to provide for the assumption of an Issuer’s or a Subsidiary Guarantor’s



 


Exhibit A-6

















 


obligations
to Holders of the Notes in case of a merger or consolidation or sale of all or
substantially all of such Issuer’s or Subsidiary Guarantor’s properties or
assets, as applicable, to add or release Subsidiary Guarantors pursuant to the
terms of the Indenture, to make any change that would provide any additional
rights or benefits to the Holders of the Notes or surrender any right or power
conferred upon the Issuers or the Subsidiary Guarantors by the Indenture that
does not adversely affect the rights under the Indenture of any such Holder, to
provide for the issuance of additional Notes in accordance with the limitations
set forth in the Indenture, to comply with the requirements of the SEC in order
to effect or maintain the qualification of the Indenture under the Trust
Indenture Act, to evidence or provide for the acceptance of appointment under
the Indenture of a successor Trustee, to add additional Events of Default, to
secure the Notes and/or the Guarantees or to provide for the reorganization of
the Partnership as any other form of entity.


 


12.
          Defaults and Remedies.  Events of Default include in summary form: (i) default
for 30 days in the payment when due of interest on the Notes; (ii) default
in payment when due of the principal of or premium, if any, on the Notes; (iii) failure
by the Partnership or any of its Restricted Subsidiaries to comply with Section 6.01
of the Indenture; (iv) failure by the Partnership to comply with the
provisions described under Section 4.09, 5.06, 5.07, 5.08, 5.09, 5.10,
5.11, 5.12, 5.13, 5.14, 5.15, 5.16 or 5.17 of the Indenture for 30 days or
under Section 5.18 of the Indenture for 90 days, in each case after notice
to the Issuers by the Trustee or to the Issuers and Trustee by Holders of at
least 25% in aggregate principal amount of the Notes then outstanding (provided
that no such notice need be given, and an Event of Default shall occur, 30 days
after a failure to comply with the covenants in Section 5.08 or 5.09 of
the Indenture, unless theretofore cured), in each case other than a failure to
purchase Notes which will constitute an Event of Default under clause (ii) above;
(v) failure by the Partnership to comply with any of its other agreements
in the Indenture for 60 days after notice to the Issuers by the Trustee or to
the Issuers and Trustee by Holders of at least 25% in aggregate principal
amount of the Notes then outstanding; (vi) default under any mortgage,
indenture or instrument under which there may be issued or by which there may
be secured or evidenced any Indebtedness for money borrowed by an Issuer or any
Restricted Subsidiary of the Partnership (or the payment of which is guaranteed
by an Issuer or any Restricted Subsidiary of the Partnership), whether such
Indebtedness or guarantee now exists, or is created after the Issue Date, if
that default (a) is caused by a failure to pay principal of or premium, if
any, or interest on such Indebtedness prior to the expiration of the grace
period provided in such Indebtedness (a “Payment Default”) or (b) results
in the acceleration of such Indebtedness prior to its express maturity and, in
each case, the principal amount of any such Indebtedness, together with the
principal amount of any other such Indebtedness under which there has been a
Payment Default or the maturity of which has been so accelerated, aggregates
$20.0 million or more; provided that if any such default is cured or waived or
any such acceleration rescinded, or such Indebtedness is repaid, within a
period of 30 days from the continuation of such default beyond the applicable
grace period or the occurrence of such acceleration, as the case may be, such
Event of Default and any consequential acceleration of the Notes shall be
automatically rescinded, so long as such rescission does not conflict with any judgment
or decree; (vii) the failure by an Issuer or any Restricted Subsidiary of
the Partnership to pay final judgments entered by courts of competent
jurisdiction aggregating in excess of $20.0 million, which judgments are not
paid, discharged or stayed for a period of 60 


 


Exhibit A-7

















 


days;
(viii) except as permitted by the Indenture, any Guarantee of a Subsidiary
Guarantor shall be held in any judicial proceeding to be unenforceable or
invalid or shall cease for any reason to be in full force and effect or any
Subsidiary Guarantor, or any Person acting on behalf of any Subsidiary
Guarantor, shall deny or disaffirm its obligations under its Guarantee; and (ix) certain
events of bankruptcy or insolvency with respect to an Issuer or any Restricted
Subsidiary of the Partnership that is a Significant Subsidiary or any group of
Restricted Subsidiaries that, taken as a whole, would constitute a Significant
Subsidiary.  If any Event of Default
occurs and is continuing, the Trustee may or at the request of the Holders of
at least 25% in aggregate principal amount of the then outstanding Notes shall
declare all the Notes to be due and payable. 
Notwithstanding the foregoing, in the case of an Event of Default
arising from certain events of bankruptcy or insolvency, with respect to an
Issuer, all outstanding Notes will become due and payable without further
action or notice.  Holders may not
enforce the Indenture or the Notes except as provided in the Indenture.  Subject to certain limitations, Holders of a
majority in aggregate principal amount of the then outstanding Notes may direct
the Trustee in its exercise of any trust or power.  The Trustee may withhold from Holders of the
Notes notice of any continuing Default or Event of Default (except a Default or
Event of Default relating to the payment of principal or interest) if it
determines that withholding notice is in their interest.


 


The
Holders of a majority in aggregate principal amount of the Notes then
outstanding by notice to the Trustee may on behalf of the Holders of all of the
Notes waive any existing Default or Event of Default and its consequences under
the Indenture except a continuing Default or Event of Default in the payment of
interest on, or the principal or premium, if any, of the Notes.  The Issuers and the Subsidiary Guarantors are
required to deliver to the Trustee annually a statement regarding compliance
with the Indenture, and the Issuers are required upon becoming aware of any
Default or Event of Default, to deliver to the Trustee a statement specifying
such Default or Event of Default.


 


13.
          Trustee Dealings with
Partnership.  The Trustee, in its
commercial banking or any other capacity, may make loans to, accept deposits
from, and perform services for the Partnership or its Affiliates, and may
otherwise deal with the Partnership or its Affiliates, as if it were not the
Trustee.


 


14.           Personal Liability of Directors,
Officers, Employees and Unitholders; No Recourse Against General Partner. No
past, present or future director, officer, partner, employee, incorporator,
manager or unitholder or other owner of Equity Interests of the Issuers, the
General Partner, or any Subsidiary Guarantor, as such, shall have any liability
for any Obligations of the Issuers or the Subsidiary Guarantors under the
Notes, the Indenture, the Guarantees or for any claim based on, in respect of,
or by reason of, such Obligations or their creation. Each Holder by accepting a
Note waives and releases all such liability. The waiver and release are part of
the consideration for issuance of the Notes.


 


15.
          Authentication.  This Note shall not be valid until
authenticated by the manual signature of the Trustee or an authenticating
agent.


 


Exhibit A-8

















 


16.
          Abbreviations.  Customary abbreviations may be used in the
name of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN
ENT (= tenants by the entireties), JT TEN (= joint tenants with right of
survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (=
Uniform Gifts to Minors Act).


 


17.
          CUSIP Numbers.  Pursuant to a recommendation promulgated by
the Committee on Uniform Security Identification Procedures, the Issuers have
caused CUSIP numbers to be printed on the Notes and the Trustee may use CUSIP
numbers in notices of redemption as a convenience to Holders.  No representation is made as to the accuracy
of such numbers either as printed on the Notes or as contained in any notice of
redemption and reliance may be placed only on the other identification numbers
placed thereon.  The Issuers will furnish
to any Holder upon written request and without charge a copy of the Indenture.


 


Requests
may be made to:


 


MarkWest
Energy Partners, L.P.


1515
Arapahoe St., Tower 2, Suite 700


Denver,
Colorado, 80202


Attention:  Chief Financial Officer


 


Exhibit A-9
















 


[FORM OF ASSIGNMENT]


 


To
assign this Note, fill in the form below: (I) or (we) assign and transfer this
Note to:


	
   

  
	
  (Insert assignee’s soc. sec. or tax I.D. no.)

  
	
   

  
	
  (Print or type name, address and zip code of assignee)

  



 


and
irrevocably appoint
                                                                                                                                                                              
to transfer this Note on the books of the Issuers.  The agent may substitute another to act for
him.


 


	
  Date:
  

  	
   

  	
   

  	
   

  	
  Your
  Signature: 

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
  (Sign
  exactly as name appears on the other side of this Note)

  



 


Signature Guarantee*


 






*                                         NOTICE: The
Signature must be guaranteed by an Institution which is a member of one of the
following recognized signature Guarantee Programs:


 


(i)
The Securities Transfer Agent Medallion Program (STAMP); (ii) The New York
Stock Exchange Medallion Program (MNSP); (iii) The Stock Exchange Medallion
Program (SEMP); or (iv) in such other guarantee program acceptable to the
Trustee.


 


Exhibit A-10

















 


OPTION OF HOLDER TO ELECT PURCHASE


 


If
you want to elect to have this Note purchased by the Partnership pursuant to
Sections 4.09 and 5.07 or Section 5.06 of the Indenture, check the box
below:


 




	
  o Sections
  4.09 and 5.07 

  	
   

  	
   

  	
  o Section 5.06

  






 


If
you want to elect to have only part of the Note purchased by the Issuers
pursuant to Sections 4.09 and 5.07 or Section 5.06 of the Indenture, state the
amount you elect to have purchased (must be a minimum of $2,000 or an integral
multiple of $1,000 in excess thereof):


 


$                       


 


 


	
  Date:
  

  	
   

  	
   

  	
  Your
  Signature:

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Date:
  

  	
   

  	
   

  	
  Your
  Signature:

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
  (Sign
  exactly as name appears on the other side of this Note)

  



 


Signature Guarantee*


 






*                                         NOTICE: The
Signature must be guaranteed by an Institution which is a member of one of the
following recognized signature Guarantee Programs:


 


(i)
The Securities Transfer Agent Medallion Program (STAMP); (ii) The New York
Stock Exchange Medallion Program (MNSP); (iii) The Stock Exchange Medallion
Program (SEMP); or (iv) in such other guarantee program acceptable to the
Trustee.


 


Exhibit A-11

















 


SCHEDULE OF EXCHANGES OF INTERESTS IN THE GLOBAL NOTE*


 


The
following exchanges of a part of this Global Note for an interest in another
Global Note or for a Certificated Note, or exchanges of a part of another
Global Note or Certificated Note for an interest in this Global Note, have been
made:


 


	
  Date of Exchange

  	
   

  	
  Signature of

  authorized signatory

  of Trustee or Note

  Custodian

  	
   

  	
  Amount of decrease

  in Principal amount

  of this Global Note

  	
   

  	
  Amount of increase

  in Principal amount

  of this Global Note

  	
   

  	
  Principal amount

  of this Global Note

  following such 

  decrease or increase

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  



 






*              This schedule should only be
included if the Note is issued in global form.


 


Exhibit A-12

















 


EXHIBIT B


FORM OF GUARANTEE NOTATION


 


Subject
to the limitations set forth in the Indenture (the “Indenture”) referred to in
the Note upon which this notation is endorsed, each of the entities listed on
Schedule A thereto (hereinafter referred to as the “Subsidiary Guarantors,”
which term includes any successor or additional Subsidiary Guarantor under the
Indenture) (i) has unconditionally guaranteed: (a) the due and punctual payment
of the principal of, premium and interest on the Notes, whether at maturity or
interest payment date, by acceleration, call for redemption or otherwise, (b)
the due and punctual payment of interest on the overdue principal of, premium
and interest if lawful, on the Notes, (c) the due and punctual payment or
performance of all other Obligations of the Issuers to the Holders or the
Trustee, all in accordance with the terms set forth in the Indenture, and (d)
in case of any extension of time of payment or renewal of any Notes or any of
such other Obligations, the prompt payment in full thereof when due or
performance thereof in accordance with the terms of the extension or renewal,
whether at Stated Maturity, by acceleration or otherwise and (ii) has agreed to
pay any and all costs and expenses (including reasonable attorneys’ fees)
incurred by the Trustee or any Holder in enforcing any rights under this
Guarantee.


 


This
Guarantee Notation is subject to the limitations set forth in the Indenture,
including Article XI thereof.


 


No
member, manager, stockholder, partner, officer, employee, director or
incorporator, as such, past, present or future, of the Subsidiary Guarantors
shall have any personal liability under this Guarantee by reason of his or its
status as such member, manager, partner, stockholder, officer, employee,
director or incorporator.


 


The
Guarantee shall be binding upon each Subsidiary Guarantor and its successors
and assigns and shall inure to the benefit of the successors and assigns of the
Trustee and the Holders and, in the event of any transfer or assignment of
rights by any Holder or the Trustee, the rights and privileges herein conferred
upon that party shall automatically extend to and be vested in such transferee
or assignee, all subject to the terms and conditions hereof.


 


Each
Guarantee shall not be valid or obligatory for any purpose until the
certificate of authentication on the Note upon which this notation of Guarantee
is noted shall have been executed by the Trustee under the Indenture by the
manual signature of one of its authorized officers.


 


The
Subsidiary Guarantors may be released from their Guarantees upon the terms and
subject to the conditions provided in the Indenture.


 


Exhibit B-1

















 


	
   

  	
  Subsidiary
  Guarantors:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  MARKWEST
  HYDROCARBON, INC.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
  Name:

  	
  Nancy
  Buese

  
	
   

  	
  Title:

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  MARKWEST ENERGY GP, L.L.C.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
  Name:

  	
  Nancy
  Buese

  
	
   

  	
  Title:

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  MASON
  PIPELINE LIMITED LIABILITY COMPANY

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Hydrocarbon, Inc.,

  
	
   

  	
   

  	
   

  	
  its
  Sole Member

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
  Name:

  	
  Nancy
  Buese

  
	
   

  	
  Title:

  	
  Senior
  Vice President and Chief Financial Officer

  



 


Exhibit B-2

















 


	
   

  	
  MARKWEST
  ENERGY OPERATING COMPANY, L.L.C.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
  its  Managing Member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
  Name:

  	
  Nancy
  Buese

  
	
   

  	
  Title:

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  WEST
  SHORE PROCESSING COMPANY, L.L.C.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Operating Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  Sole Member and Manager

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
  Name:

  	
  Nancy
  Buese

  
	
   

  	
  Title:

  	
  Senior
  Vice President and Chief Financial Officer

  



 


Exhibit B-3
















 


	
   

  	
  MARKWEST
  BLACKHAWK, L.L.C.

  
	
   

  	
  MARKWEST
  ENERGY APPALACHIA, L.L.C.

  
	
   

  	
  MARKWEST
  ENERGY EAST TEXAS GAS COMPANY, L.L.C.

  
	
   

  	
  MARKWEST
  GAS MARKETING, L.L.C.

  
	
   

  	
  MARKWEST
  GAS SERVICES, L.L.C.

  
	
   

  	
  MARKWEST
  JAVELINA COMPANY, L.L.C.

  
	
   

  	
  MARKWEST
  JAVELINA PIPELINE COMPANY, L.L.C.

  
	
   

  	
  MARKWEST
  LIBERTY GAS GATHERING, L.L.C.

  
	
   

  	
  MARKWEST
  MARKETING, L.L.C.

  
	
   

  	
  MARKWEST
  NEW MEXICO, L.L.C.

  
	
   

  	
  MARKWEST PINNACLE, L.L.C.

  
	
   

  	
  MARKWEST
  PIPELINE COMPANY, L.L.C.

  
	
   

  	
  MARKWEST
  PNG UTILITY, L.L.C.

  
	
   

  	
  MARKWEST
  POWER TEX, L.L.C.

  
	
   

  	
  MARKWEST
  TEXAS PNG UTILITY, L.L.C.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Operating Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  Sole Member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
  Name:

  	
  Nancy
  Buese

  
	
   

  	
  Title:

  	
  Senior
  Vice President and Chief Financial Officer

  



 


Exhibit B-4

















 


	
  MARKWEST
  MICHIGAN PIPELINE COMPANY, L.L.C.

  	
   

  
	
   

  	
  MARKWEST
  OKLAHOMA GAS COMPANY, L.L.C.

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Operating Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
  Name:

  	
  Nancy
  Buese

  
	
   

  	
  Title:

  	
  Senior
  Vice President and Chief Financial Officer

  



 


Exhibit B-5

















 


	
   

  	
  MATREX,
  L.L.C.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  West
  Shore Processing Company, L.L.C.

  
	
   

  	
   

  	
   

  	
  its
  Sole Member and Manager

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Operating Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  Sole Member and Manager

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
  Name:

  	
  Nancy
  Buese

  
	
   

  	
  Title:

  	
  Senior
  Vice President and Chief Financial Officer

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  MARKWEST MCALESTER, L.L.C.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Oklahoma Gas Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  Sole Member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Operating Company, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest
  Energy Partners, L.P.,

  
	
   

  	
   

  	
   

  	
  its
  Managing Member

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
  MarkWest Energy GP, L.L.C.,

  
	
   

  	
   

  	
   

  	
  its
  General Partner

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
  Name:

  	
  Nancy
  Buese

  
	
   

  	
  Title:

  	
  Senior
  Vice President and Chief Financial Officer

  



 


Exhibit B-6

















 


EXHIBIT C


 


FORM OF SUPPLEMENTAL INDENTURE


 


This
SUPPLEMENTAL INDENTURE, dated as of            
  ,      is among MarkWest Energy Partners, L.P.,
a Delaware limited partnership (the “Partnership”), MarkWest Energy Finance
Corporation, a Delaware corporation (“MarkWest Finance” and, together with the
Partnership, the “Issuers”), each of the parties identified under the caption “Subsidiary
Guarantors” on the signature page hereto (the “Subsidiary Guarantors”) and
Wells Fargo Bank, National Association, a national banking association, as
Trustee.


 


RECITALS


 


WHEREAS,
the Issuers, the initial Subsidiary Guarantors and the Trustee entered into an
Indenture, dated as of November 2, 2010 (as supplemented and amended by the
First Supplemental Indenture dated as of November 2, 2010, the “Indenture”),
pursuant to which the Issuers have issued $            
in principal amount of 63⁄4% Senior Notes due 2020 (the “Notes”);


 


WHEREAS,
Section 10.01 of the Indenture provides that the Issuers, the Subsidiary
Guarantors and the Trustee may amend or supplement the Indenture in order to
add Subsidiary Guarantors pursuant to Section 5.13 or 6.01(c) thereof, without
the consent of the Holders of the Notes; and


 


WHEREAS,
all acts and things prescribed by the Indenture, by law and by the Certificate
of Incorporation and the Bylaws (or comparable constituent documents) of the
Issuers, of the Subsidiary Guarantors and of the Trustee necessary to make this
Supplemental Indenture a valid instrument legally binding on the Issuers, the
Subsidiary Guarantors and the Trustee, in accordance with its terms, have been
duly done and performed;


 


NOW,
THEREFORE, to comply with the provisions of the Indenture and in consideration
of the above premises, the Issuers, the Subsidiary Guarantors and the Trustee
covenant and agree for the equal and proportionate benefit of the respective Holders
of the Notes as follows:


ARTICLE 1


 


This
Supplemental Indenture is supplemental to the Indenture and does and shall be
deemed to form a part of, and shall be construed in connection with and as part
of, the Indenture for any and all purposes.


 


This
Supplemental Indenture shall become effective immediately upon its execution
and delivery by each of the Issuers, the Subsidiary Guarantors and the Trustee.


 


Exhibit C-1

















 


ARTICLE II


 


From
this date, in accordance with Section 4.13 or 5.01(c) and by executing this
Supplemental Indenture, the Guarantors whose signatures appear below are
subject to the provisions of the Indenture to the extent provided for in
Article XI thereunder.


 


ARTICLE III


 


Except
as specifically modified herein, the Indenture and the Notes are in all
respects ratified and confirmed (mutatis
mutandis) and shall remain in full force and effect in accordance
with their terms with all capitalized terms used herein without definition
having the same respective meanings ascribed to them as in the Indenture.


 


The
Trustee accepts the amendments of the Indenture effected by this Supplemental
Indenture and agrees to execute the trust created by the Indenture as hereby
amended, but on the terms and conditions set forth in the Indenture, including
the terms and provisions defining and limiting the liabilities and
responsibilities of the Trustee, which terms and provisions shall in like
manner define and limit its liabilities and responsibilities in the performance
of the trust created by the Indenture as hereby amended, and without limiting
the generality of the foregoing, the Trustee shall not be responsible in any
manner whatsoever for or with respect to any of the recitals or statements
contained herein, all of which recitals or statements are made solely by the
Issuers and the Subsidiary Guarantors, and the Trustee makes no representation
with respect to any such matters. 
Additionally, the Trustee makes no representations as to the validity or
sufficiency of this Supplemental Indenture


 


THIS
SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH,
THE LAWS OF THE STATE OF NEW YORK.


 


The
parties may sign any number of copies of this Supplemental Indenture.  Each signed copy shall be an original, but
all of such executed copies together shall represent the same agreement.


 


[NEXT PAGE IS SIGNATURE PAGE]


 


Exhibit C-2

















 


IN
WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to
be duly executed, all as of the date first written above.


 


	
   

  	
  MARKWEST
  ENERGY PARTNERS, L.P.

  
	
   

  	
  BY:
  

  	
  MARKWEST
  ENERGY GP, L.L.C.,

  
	
   

  	
   

  	
  ITS
  GENERAL PARTNER

  
	
   

  	
   

  	
   

  
	
   

  	
  By

  	
   

  
	
   

  	
   

  	
  Name:

  	
   

  
	
   

  	
   

  	
  Title:

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  MARKWEST
  ENERGY FINANCE CORPORATION

  
	
   

  	
  By:

  	
   

  
	
   

  	
  Name:

  	
   

  
	
   

  	
  Title:

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  SUBSIDIARY
  GUARANTORS

  
	
   

  	
  [                                                                                     ]

  
	
   

  	
   

  	
   

  
	
   

  	
  By

  	
   

  
	
   

  	
   

  	
  Name:

  	
   

  
	
   

  	
   

  	
  Title:

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  WELLS
  FARGO BANK, NATIONAL ASSOCIATION,

  
	
   

  	
  as
  Trustee

  
	
   

  	
   

  	
   

  
	
   

  	
  By

  	
   

  
	
   

  	
   

  	
  Name:

  	
   

  
	
   

  	
   

  	
  Title:

  	
   

  



 


Exhibit C-3