Exhibit 10.2


 


REGISTRATION RIGHTS
AGREEMENT



by and among



MARKWEST ENERGY PARTNERS, L.P.



AND



THE PURCHASERS PARTY HERETO


 





















 


REGISTRATION RIGHTS AGREEMENT


 


THIS REGISTRATION RIGHTS AGREEMENT (this “Agreement”)
is made and entered into as of December 18, 2007, by and among MARKWEST
ENERGY PARTNERS, L.P. (“MarkWest”) and each of the purchasers set forth
on Schedule A hereto (each a “Purchaser” and collectively, the “Purchasers”).  Capitalized terms used herein without
definition shall have the meanings given to them in the Purchase Agreement.


 


This Agreement is made in connection with the Closing
of the issuance and sale of the Purchased Units pursuant to the Unit Purchase
Agreement, dated as of December 18, 2007, by and among MarkWest, MarkWest
Energy GP, L.L.C. and the Purchasers (the “Purchase Agreement”).  MarkWest has agreed to provide the
registration and other rights set forth in this Agreement for the benefit of
the Purchasers pursuant to Section 2.03(a)(iv) of the Purchase
Agreement. In consideration of the mutual covenants and agreements set forth
herein and in the Purchase Agreement and for good and valuable consideration,
the receipt and sufficiency of which is hereby acknowledged by each party
hereto, the parties hereby agree as follows:


 


ARTICLE I

DEFINITIONS


 


Section 1.01           Definitions.  The terms set forth below are used herein as
so defined:


 


“Affiliate” means, with respect to a specified
Person, any other Person, directly or indirectly controlling, controlled by or
under direct or indirect common control with such specified Person.  For purposes of this definition, “control”
(including, with correlative meanings, “controlling,” “controlled by,” and “under
common control with”) means the power to direct or cause the direction of the
management and policies of such Person, directly or indirectly, whether through
the ownership of voting securities, by contract or otherwise.


 


“Agreement” has the meaning specified therefor
in the introductory paragraph hereof.


 


“Business Day” means any day other than a
Saturday, Sunday, or a legal holiday for commercial banks in New York, New
York.


 


“Commission” means the United States Securities
and Exchange Commission.


 


“Common Units” means the common units of
MarkWest.


 


“Effectiveness Period” means the period beginning
on the date a Registration Statement first is declared effective under the
Securities Act and ending on the date all Registrable Securities covered by
such Registration Statement have been distributed in the manner set forth and
as contemplated in such Registration Statement.


 


“Exchange Act” shall mean the Securities
Exchange Act of 1934, as amended from time to time, and the rules and
regulations of the Commission promulgated thereunder.


 


“Holder” means the record holder of any
Registrable Securities.


 


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“Included Registrable Securities” has the
meaning specified therefor in Section 2.02(a) of this Agreement.


 


“Liquidated Damages Amount” means an amount
equal to 1.00% of the product of $31.50 times the number of Registrable
Securities held by such Holder per 30-day period.  The Liquidated Damages Amount for any period
of less than 30 days shall be prorated by multiplying the Liquidated Damages
Amount to be paid in a full 30-day period by a fraction, the numerator of which
is the number of days for which such liquidated damages are owed, and the
denominator of which is 30.


 


“Losses” has the meaning specified therefor in Section 2.08(a) of
this Agreement.


 


“Managing Underwriter” means, with respect to
any Underwritten Offering, the book running lead manager of such Underwritten
Offering.


 


“MarkWest” has the meaning specified therefor
in the introductory paragraph of this Agreement.


 


“MarkWest Hydrocarbon” means MarkWest
Hydrocarbon, Inc., a Delaware corporation.


 


“Opt Out Notice” has the meaning specified
therefor in Section 2.02(a).


 


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


 


“Prior Holders” means each investor party to (i) the
Registration Rights Agreement dated April 9, 2007, by and among MarkWest
and each party listed on Schedule A thereto, (ii) the Registration Rights
Agreement dated November 9, 2005, by and among MarkWest and each party
listed on Schedule A thereto or (iii) each investor party to the
Registration Rights Agreement dated December 23, 2005 by and among
MarkWest and each party listed on Schedule A thereto.


 


“Purchase Agreement” has the meaning specified
therefor in the introductory paragraph of this Agreement.


 


“Purchased Units” shall have the meaning set
forth in the Purchase Agreement.


 


“Purchaser” and “Purchasers” each has
the meaning specified therefor in the introductory paragraph of this Agreement.


 


“Registrable Securities” means the Common Units
comprising the Purchased Units until such time as such securities cease to be
Registrable Securities pursuant to Section 1.02 hereof.


 


“Registration Expenses” has the meaning
specified therefor in Section 2.07(a) of this Agreement.


 


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“Registration Statement” means a registration
statement under the Securities Act to permit the public sale of securities from
time to time.


 


“Securities Act” means the Securities Act of
1933, as amended from time to time, and the rules and regulations of the
Commission promulgated thereunder.


 


“Selling Expenses” has the meaning specified
therefor in Section 2.07(a) of this Agreement.


 


“Selling Holder” means a Holder who is selling
Registrable Securities pursuant to a Registration Statement.


 


“Selling Holder Indemnified Person” has the
meaning specified in Section 2.08(a) of this Agreement.


 


“Underwritten Offering” means an offering
(including an offering pursuant to a Registration Statement) in which Common
Units are sold to an underwriter on a firm commitment basis for reoffering to
the public or an offering that is a “bought deal” with one or more investment
banks.


 


Section 1.02           Registrable
Securities.  Any Registrable Security
will cease to be a Registrable Security when (a) a Registration Statement
covering such Registrable Security becomes or is declared effective by the
Commission and such Registrable Security has been sold or disposed of pursuant
to such effective Registration Statement; (b) such Registrable Security
has been disposed of pursuant to any section of Rule 144 (or any similar
provision then in force) under the Securities Act; (c) such Registrable
Security is held by MarkWest or one of its subsidiaries; or (d) such
Registrable Security has been sold in a private transaction in which the
transferor’s rights under this Agreement are not assigned to the transferee of
such securities pursuant to Section 2.10 hereof.


 


Section 1.03           Rights
and Obligations.  Except for the
rights and obligations under Section 2.08 herein, all rights and
obligations of each Purchaser under this Agreement, and all rights and
obligations of MarkWest under this Agreement with respect to such Purchaser,
shall terminate when such Purchaser is no longer a Holder.


 


ARTICLE II

REGISTRATION RIGHTS


 


Section 2.01           Reserved.


 


Section 2.02           Piggyback Rights.


 


(a)           Participation. 
If MarkWest, other than in connection with the Hydrocarbon Acquisition,
at any time proposes to (i) file a prospectus supplement to an effective
shelf registration statement with respect to an Underwritten Offering of Common
Units, (ii) register any Common Units for its own account for sale to the
public in an Underwritten Offering other than, in the case of this
clause (ii), (a) a registration relating solely to employee benefit
plans, (b) a registration relating solely to a Rule 145 transaction,
or (c) a registration on any registration 


 


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form which does not permit secondary sales, or (iii) register any
Common Units on behalf of any other person for the sale of Common Units in an
Underwritten Offering, then, as soon as practicable following the engagement of
counsel by MarkWest to prepare the documents to be used in connection with an
Underwritten Offering, MarkWest shall give written notice of such proposed
Underwritten Offering to the Holders and such notice shall offer the Holders
the opportunity to include in such Underwritten Offering such number of
Registrable Securities as each such Holder may request in writing; provided,
however, that MarkWest shall not be required to offer such opportunity
to Holders to the extent MarkWest has been advised by the Managing Underwriter
that the inclusion of Registrable Securities for sale for the benefit of the
Holders will have a materially adverse effect on the price, timing or
distribution of the Common Units.  The
notice required to be provided in this Section 2.02(a) to Holders
shall be provided on a Business Day pursuant to Section 3.01 hereof and
receipt of such notice shall be confirmed by the Holder.  Subject to Section 2.02(b), MarkWest
shall include in such Underwritten Offering all such Registrable Securities (“Included
Registrable Securities”) with respect to which MarkWest has received
requests within one Business Day after MarkWest’s notice has been delivered in
accordance with Section 3.01.  If no
request for inclusion from a Holder is received within the specified time, such
Holder shall have no further right to participate in such Underwritten
Offering.  If, at any time after giving
written notice of its intention to undertake an Underwritten Offering and prior
to the closing of such Underwritten Offering, MarkWest shall determine for any
reason not to undertake or to delay such Underwritten Offering, MarkWest may,
at its election, give written notice of such determination to the Selling
Holders and, (i) in the case of a determination not to undertake such
Underwritten Offering, shall be relieved of its obligation to sell any Included
Registrable Securities in connection with such terminated Underwritten
Offering, and (ii) in the case of a determination to delay such
Underwritten Offering, shall be permitted to delay offering any Included
Registrable Securities for the same period as the delay in the Underwritten
Offering. Any Selling Holder shall have the right to withdraw such Selling
Holder’s request for inclusion of such Selling Holder’s Registrable Securities
in such Underwritten Offering by giving written notice to MarkWest of such
withdrawal up to and including the time of pricing of such Underwritten
Offering.  No Holders shall be entitled
to participate in any such Underwritten Offering under this Section 2.02(a) unless
such Holder (together with any Affiliate that owns Registrable Securities and
is a Selling Holder) holds at least $5 million of Registrable Securities in
such offering (determined by multiplying the number of Registrable Securities
owned by the average of the closing price for Common Units for the ten (10) trading
days preceding the date of such notice). 
Notwithstanding the foregoing, any Holder may deliver written notice (an
“Opt Out Notice”) to the Company requesting that such Holder not receive
notice from the Company of any proposed Underwritten Offering; provided that
any such Holder may later revoke any such notice.


 


(b)           Priority of
Piggyback Registration.  If the
Managing Underwriter or underwriters of any proposed Underwritten Offering of
Common Units advises MarkWest in writing that the total amount of Common Units
which the Selling Holders and any other Persons intend to include in such
Underwritten Offering exceeds the number which can be sold in such offering
without being likely to have a materially adverse effect on the price, timing
or distribution of the Common Units offered or the market for the Common Units,
then the Common Units to be included in such Underwritten Offering shall
include the number of Common Units that such Managing Underwriter or
underwriters advises MarkWest can be sold without having such materially
adverse effect, with such number to be allocated pro  rata among
the Selling Holders 


 


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and
Prior Holders having a right to (and having requested to) participate in such
Underwritten Offering pursuant to a valid and enforceable registration rights
agreement with MarkWest (based, for each such Selling Holder or Prior Holder,
as applicable, on the percentage derived by dividing (A) the number of
Registrable Securities or other registrable securities entitled to be included
in an Underwritten Offering, proposed to be sold by such Selling Holder or
Prior Holder in such offering; by (B) the aggregate number of Common Units
proposed to be sold by, as the case may be, the Selling Holders and Prior
Holders participating in the Underwritten Offering).


 


(c)           Termination of
Piggyback Rights.  The right to
piggyback on an Underwritten Offering granted pursuant to this Section 2.02
shall be unlimited in number and shall terminate the later of (i) two
years following the Closing Date and (ii) the date on which all
Registrable Securities cease to be Registrable Securities hereunder in
accordance with Section 1.02.


 


Section 2.03           Underwritten
Offering.


 


(a)           Request by
Holders.  At any time more than 60
days following (i) the consummation of the Hydrocarbon Acquisition or (ii) the
termination of the Hydrocarbon Purchase Agreement, upon the written request of
one or more Holders, MarkWest shall engage underwriters and enter into an
underwriting agreement in customary form with the Managing Underwriter or
underwriters, which shall include, among other provisions, indemnities to the
effect and to the extent provided in Section 2.08, and shall take all such
other reasonable actions as are requested by the Managing Underwriter in order
to expedite or facilitate the registration and disposition of the Registrable
Securities; provided, however, such Holders reasonably anticipate
gross proceeds from such offering of at least twenty million dollars
($20,000,000), in the aggregate (determined by multiplying the number of
Registrable Securities owned by the average of the closing price for Common
Units for the ten (10) trading days preceding the date of such
request).  MarkWest shall be required to
cause appropriate officers of MarkWest or its Affiliates to participate in a “road
show” or similar marketing effort being conducted by such underwriter with
respect to such Underwritten Offering only if the Holders reasonably anticipate
gross proceeds from such Underwritten Offering of at least forty million
dollars ($40,000,000) (determined by multiplying the number of Registrable
Securities owned by the average of the closing price for Common Units for the
ten (10) trading days preceding the date of such request).


 


(b)           General
Procedures.  In connection with any
Underwritten Offering under this Agreement (except for Underwritten Offerings
pursuant to Section 2.03(a)), MarkWest shall be entitled to select the
Managing Underwriter or underwriters, each of which must be a
nationally-recognized firm.  In the case
of an Underwritten Offering pursuant to Section 2.03(a) hereof, the
Selling Holders in such Underwritten Offering shall be entitled to select the
Managing Underwriter or underwriters, each of which must be a nationally
recognized firm.  In the event there is
more than one Selling Holder, each Selling Holder shall be entitled to vote for
the selection of the Managing Underwriter and shall be entitled to the number
of votes equal to the number of Registrable Securities being offered for sale
pursuant to such Underwritten Offering, with the majority vote of such Selling
Holders determining the Managing Underwriter. 
In connection with an Underwritten Offering under Section 2.01 or
2.02 hereof, each Selling Holder and MarkWest shall be obligated to enter into
an underwriting agreement which contains such representations, covenants,
indemnities and other rights and obligations as are customary in 


 


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underwriting
agreements for firm commitment offerings of securities.  No Selling Holder may participate in such
Underwritten Offering unless such Selling Holder agrees to sell its Registrable
Securities on the basis provided in such underwriting agreement and completes
and executes all questionnaires, powers of attorney, indemnities and other
documents reasonably required under the terms of such underwriting
agreement.  Each Selling Holder may, at
its option, require that any or all of the representations and warranties by,
and the other agreements on the part of, MarkWest to and for the benefit of
such underwriters also be made to and for such Selling Holder’s benefit and
that any or all of the conditions precedent to the obligations of such
underwriters under such underwriting agreement also be conditions precedent to
its obligations. No Selling Holder shall be required to make any
representations or warranties to or agreements with MarkWest or the underwriters
other than representations, warranties or agreements regarding such Selling
Holder and its ownership of the securities being registered on its behalf and
its intended method of distribution and any other representation required by
law.  If any Selling Holder disapproves
of the terms of an underwriting, such Selling Holder may elect to withdraw
therefrom by notice to MarkWest and the Managing Underwriter; provided, however,
that such withdrawal must be made up to and including the time of pricing to be
effective.  No such withdrawal or
abandonment shall affect MarkWest’s obligation to pay Registration Expenses.


 


Section 2.04           Registration
Procedures.  In connection with its
obligations contained in Sections 2.02 and 2.03, MarkWest will, as
expeditiously as possible:


 


(a)           prepare and file
with the Commission such amendments and supplements to a Registration Statement
and the prospectus used in connection therewith as may be necessary to keep
such Registration Statement effective for the Effectiveness Period and as may
be necessary to comply with the provisions of the Securities Act with respect
to the disposition of all securities covered by the Registration Statement;


 


(b)           furnish to each
Selling Holder (i) as far in advance as reasonably practicable before
filing any registration statement contemplated by this Agreement or any
supplement or amendment thereto, upon request, copies of reasonably complete
drafts of all such documents proposed to be filed (including exhibits and each
document incorporated by reference therein to the extent then required by the rules and
regulations of the Commission), and provide each such Selling Holder the
opportunity to object to any information pertaining to such Selling Holder and
its plan of distribution that is contained therein and make the corrections
reasonably requested by such Selling Holder with respect to such information
prior to filing the Registration Statement or supplement or amendment thereto,
and (ii) such number of copies of the Registration Statement and the
prospectus included therein and any supplements and amendments thereto as such
Selling Holders may reasonably request in order to facilitate the public sale
or other disposition of the Registrable Securities covered by such Registration
Statement;


 


(c)           if applicable, use
its commercially reasonable efforts to register or qualify the Registrable
Securities covered by a Registration Statement under the securities or blue sky
laws of such jurisdictions as the Selling Holders or, in the case of an
Underwritten Offering, the Managing Underwriter, shall reasonably request,
provided that MarkWest will not be required to qualify generally to transact
business in any jurisdiction where it is not then required to so 


 


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qualify
or to take any action which would subject it to general service of process in
any such jurisdiction where it is not then so subject;


 


(d)           promptly notify each
Selling Holder and each underwriter, at any time when a prospectus relating
thereto is required to be delivered under the Securities Act, of (i) the
filing of a Registration Statement or any prospectus or prospectus supplement
to be used in connection therewith, or any amendment or supplement thereto, and
when the same has become effective; and (ii) any written comments from the
Commission with respect to any filing referred to in clause (i) and any
written request by the Commission for amendments or supplements to a
Registration Statement or any prospectus or prospectus supplement thereto;


 


(e)           immediately notify
each Selling Holder and each underwriter, at any time when a prospectus
relating thereto is required to be delivered under the Securities Act, of (i) the
happening of any event as a result of which the prospectus or prospectus supplement
contained in a Registration Statement, as then in effect, includes an untrue
statement of a material fact or omits to state any material fact required to be
stated therein or necessary to make the statements therein not misleading in
the light of the circumstances then existing; (ii) the issuance or threat
of issuance by the Commission of any stop order suspending the effectiveness of
a Registration Statement, or the initiation of any proceedings for that
purpose; or (iii) the receipt by MarkWest of any notification with respect
to the suspension of the qualification of any Registrable Securities for sale
under the applicable securities or blue sky laws of any jurisdiction.  Following the provision of such notice,
MarkWest agrees to as promptly as practicable amend or supplement the
prospectus or prospectus supplement or take other appropriate action so that
the prospectus or prospectus supplement does not include an untrue statement of
a material fact or omit to state a material fact required to be stated therein
or necessary to make the statements therein not misleading in the light of the
circumstances then existing and to take such other action as is necessary to
remove a stop order, suspension, threat thereof or proceedings related thereto;


 


(f)            furnish to each
Selling Holder copies of any and all transmittal letters or other
correspondence with the Commission or any other governmental agency or
self-regulatory body or other body having jurisdiction (including any domestic
or foreign securities exchange) relating to such offering of Registrable
Securities;


 


(g)           in the case of an
Underwritten Offering, furnish upon request to a Selling Holder, (i) an
opinion of counsel for MarkWest, dated the effective date of the applicable
Registration Statement or the date of any amendment or supplement thereto, and
a letter of like kind dated the date of the closing under the underwriting
agreement, and (ii) a “cold comfort” letter, dated the effective date of
the applicable Registration Statement or the date of any amendment or
supplement thereto and a letter of like kind dated the date of the closing
under the underwriting agreement, in each case, signed by the independent
public accountants who have certified MarkWest’s financial statements included
or incorporated by reference into the applicable Registration Statement, and
each of the opinion and the “cold comfort” letter shall be in customary form
and covering substantially the same matters with respect to such Registration
Statement (and the prospectus and any prospectus supplement included therein)
and as are customarily covered in opinions of issuer’s counsel and in
accountants’ letters delivered to the 


 


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underwriters
in Underwritten Offerings of securities, such other matters as such
underwriters may reasonably request;


 


(h)           otherwise use its
commercially reasonable efforts to comply with all applicable rules and
regulations of the Commission, and make available to its security holders, as
soon as reasonably practicable, an earnings statement covering the period of at
least 12 months, but not more than 18 months, beginning with the first full
calendar month after the effective date of such Registration Statement, which
earnings statement shall satisfy the provisions of Section 11(a) of
the Securities Act and Rule 158 promulgated thereunder;


 


(i)            make available to
the appropriate representatives of the Managing Underwriter and Selling Holders
access to such information and MarkWest personnel as is reasonable and
customary to enable such parties to establish a due diligence defense under the
Securities Act; provided that MarkWest need not disclose any information to any
such representative unless and until such representative has entered into a
confidentiality agreement with MarkWest;


 


(j)            cause all such
Registrable Securities registered pursuant to this Agreement to be listed on
each securities exchange or nationally recognized quotation system on which
similar securities issued by MarkWest are then listed;


 


(k)           use its commercially
reasonable efforts to cause the Registrable Securities to be registered with or
approved by such other governmental agencies or authorities as may be necessary
by virtue of the business and operations of MarkWest to enable the Selling Holders
to consummate the disposition of such Registrable Securities;


 


(l)            provide a transfer
agent and registrar for all Registrable Securities covered by such Registration
Statement not later than the effective date of such Registration Statement; and


 


(m)          enter into customary
agreements and take such other actions as are reasonably requested by the
Selling Holders or the underwriters, if any, in order to expedite or facilitate
the disposition of such Registrable Securities.


 


Each Selling Holder, upon receipt of notice from
MarkWest of the happening of any event of the kind described in subsection (e) of
this Section 2.04, shall forthwith discontinue disposition of the
Registrable Securities until such Selling Holder’s receipt of the copies of the
supplemented or amended prospectus contemplated by subsection (e) of this Section 2.04
or until it is advised in writing by MarkWest that the use of the prospectus
may be resumed, and has received copies of any additional or supplemental
filings incorporated by reference in the prospectus, and, if so directed by
MarkWest, such Selling Holder will, or will request the Managing Underwriter or
underwriters, if any, to deliver to MarkWest (at MarkWest’s expense) all copies
in their possession or control, other than permanent file copies then in such
Selling Holder’s possession, of the prospectus covering such Registrable
Securities current at the time of receipt of such notice.


 


Section 2.05           Cooperation
by Holders.  MarkWest shall have no
obligation to include Registrable Securities of a Holder in a Registration
Statement who has failed to timely furnish such information which, in the
opinion of counsel to MarkWest, is reasonably required in order 


 


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for
a Registration Statement or prospectus supplement, as applicable, to comply
with the Securities Act.


 


Section 2.06           Restrictions
on Public Sale by Holders of Registrable Securities.  Each Holder of Registrable Securities who is
included in a Registration Statement agrees not to effect any public sale or
distribution of Registrable Securities during the 30 calendar day period
beginning on the date of a prospectus supplement or prospectus filed with the
Commission with respect to the pricing of an Underwritten Offering, provided
that the duration of the foregoing restrictions shall be no longer than the
duration of the shortest restriction generally imposed by the underwriters on
the officers or directors or any other unitholder of MarkWest on whom a
restriction is imposed; and provided further, that the restrictions under this Section 2.06
shall not apply (i) to any Holder that is not otherwise eligible to
participate in such Underwritten Offering pursuant to Section 2.02(a), (ii) to
the sale or distribution of Registrable Securities in such Underwritten
Offering pursuant to Section 2.02(a) or (iii) has submitted an
Opt Out Notice.


 


Section 2.07           Expenses.


 


(a)           Certain
Definitions.  “Registration
Expenses” means all expenses incident to MarkWest’s performance under or
compliance with this Agreement to effect the registration of Registrable
Securities in a Registration Statement, or otherwise pursuant to Section 2.03,
and the disposition of such securities, including, without limitation, all
registration, filing, securities exchange listing and American Stock Exchange
or other securities exchange or listing fees, all registration, filing,
qualification and other fees and expenses of complying with securities or blue
sky laws, fees of the National Association of Securities Dealers, Inc.,
transfer taxes and fees of transfer agents and registrars, all word processing,
duplicating and printing expenses, the fees and disbursements of counsel and
independent public accountants for MarkWest, including the expenses of any
special audits or “cold comfort” letters required by or incident to such
performance and compliance.  Except as
otherwise provided in Section 2.08 hereof, MarkWest shall not be
responsible for legal fees incurred by Holders in connection with the exercise
of such Holders’ rights hereunder.  In
addition, MarkWest shall not be responsible for any “Selling Expenses,”
which means all underwriting fees, discounts and selling commissions allocable
to the sale of the Registrable Securities.


 


(b)           Expenses.  MarkWest will pay all Registration Expenses
in connection with any Registration Statement, whether or not the applicable
Registration Statement becomes effective or any sale is made pursuant to such
Registration Statement. Each Selling Holder shall pay all Selling Expenses in
connection with any sale of its Registrable Securities hereunder.


 


Section 2.08           Indemnification.


 


(a)           By MarkWest.  In the event of a registration of any
Registrable Securities under the Securities Act pursuant to this Agreement,
MarkWest will indemnify and hold harmless each Selling Holder thereunder, its
Affiliates that own Registrable Securities and their respective directors and
officers, and each underwriter, pursuant to the applicable underwriting
agreement with such underwriter, of Registrable Securities thereunder and each
Person, if any, who controls such Selling Holder or underwriter within the
meaning of the Securities Act and the Exchange Act (collectively, the “Selling
Holder Indemnified Persons”), against any losses, claims, 


 


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damages,
expenses or liabilities (including reasonable attorneys’ fees and expenses)
(collectively, “Losses”), joint or several, to which such Selling Holder
Indemnified Person may become subject under the Securities Act, the Exchange
Act or otherwise, insofar as such Losses (or actions or proceedings, whether
commenced or threatened, in respect thereof) arise out of or are based upon any
untrue statement or alleged untrue statement of any material fact contained in
a Registration Statement or any other registration statement contemplated by
this Agreement, any preliminary prospectus or final prospectus contained
therein, or any amendment or supplement thereof, or arise out of or are based
upon the omission or alleged omission to state therein a material fact required
to be stated therein or necessary to make the statements therein (in the case
of a prospectus, in light of the circumstances under which they were made) not
misleading, and will reimburse each such Selling Holder Indemnified Person for
any legal or other expenses reasonably incurred by them in connection with
investigating or defending any such Loss or actions or proceedings as such
expenses are incurred; provided, however, that MarkWest will not
be liable in any such case if and to the extent that any such Loss arises out
of or is based upon an untrue statement or alleged untrue statement or omission
or alleged omission so made in conformity with information furnished by such
Selling Holder Indemnified Person in writing specifically for use in a
Registration Statement or such other registration statement, or prospectus
supplement, as applicable. Such indemnity shall remain in full force and effect
regardless of any investigation made by or on behalf of such Selling Holder
Indemnified Person, and shall survive the transfer of such securities by such
Selling Holder.


 


(b)           By Each Selling
Holder.  Each Selling Holder agrees
severally and not jointly to indemnify and hold harmless MarkWest, its
Affiliates and their respective directors and officers, and each Person, if
any, who controls MarkWest within the meaning of the Securities Act or of the
Exchange Act to the same extent as the foregoing indemnity from MarkWest to the
Selling Holders, but only with respect to information regarding such Selling
Holder furnished in writing by or on behalf of such Selling Holder expressly
for inclusion in a Registration Statement or prospectus supplement relating to
the Registrable Securities, or any amendment or supplement thereto; provided,
however, that the liability of each Selling Holder shall not be greater
in amount than the dollar amount of the proceeds (net of any Selling Expenses)
received by such Selling Holder from the sale of the Registrable Securities
giving rise to such indemnification.


 


(c)           Notice.  Promptly after receipt by an indemnified
party hereunder of notice of the commencement of any action, such indemnified
party shall, if a claim in respect thereof is to be made against the
indemnifying party hereunder, notify the indemnifying party in writing thereof,
but the omission so to notify the indemnifying party shall not relieve it from
any liability which it may have to any indemnified party other than under this Section 2.08.  In any action brought against any indemnified
party, it shall notify the indemnifying party of the commencement thereof.  The indemnifying party shall be entitled to
participate in and, to the extent it shall wish, to assume and undertake the
defense thereof with counsel reasonably satisfactory to such indemnified party
and, after notice from the indemnifying party to such indemnified party of its
election so to assume and undertake the defense thereof, the indemnifying party
shall not be liable to such indemnified party under this Section 2.08 for
any legal expenses subsequently incurred by such indemnified party in
connection with the defense thereof other than reasonable costs of
investigation and of liaison with counsel so selected; provided, however,
that, (i) if the indemnifying party has failed to assume the defense and
employ counsel or (ii) if the defendants in any such action include both
the indemnified party and the indemnifying party and counsel to 


 


10





















 


the
indemnified party shall have concluded that there may be reasonable defenses
available to the indemnified party that are different from or additional to
those available to the indemnifying party, or if the interests of the
indemnified party reasonably may be deemed to conflict with the interests of
the indemnifying party, then the indemnified party shall have the right to
select a separate counsel and to assume such legal defense and otherwise to
participate in the defense of such action, with the reasonable expenses and
fees of such separate counsel and other reasonable expenses related to such
participation to be reimbursed by the indemnifying party as incurred.  Notwithstanding any other provision of this
Agreement, no indemnifying party, without the consent of the indemnified party,
shall settle any action in respect for which indemnification may be sought
hereunder, unless the settlement thereof imposes no liability or obligation on,
and includes a complete and unconditional release from all liability of, the
indemnified party.


 


(d)           Contribution.  If the indemnification provided for in this Section 2.08
is held by a court or government agency of competent jurisdiction to be
unavailable to MarkWest or any Selling Holder or is insufficient to hold them
harmless in respect of any Losses, then each such indemnifying party, in lieu
of indemnifying such indemnified party, shall contribute to the amount paid or
payable by such indemnified party as a result of such Losses as between
MarkWest on the one hand and such Selling Holder on the other, in such
proportion as is appropriate to reflect the relative fault of MarkWest on the
one hand and of such Selling Holder (or other indemnified party) on the other
in connection with the statements or omissions which resulted in such Losses,
as well as any other relevant equitable considerations; provided, however,
that in no event shall such Selling Holder be required to contribute an
aggregate amount in excess of the dollar amount of proceeds (net of Selling
Expenses) received by such Selling Holder from the sale of Registrable
Securities giving rise to such indemnification. 
The relative fault of MarkWest on the one hand and each Selling Holder
on the other shall be determined by reference to, among other things, whether
the untrue or alleged untrue statement of a material fact or the omission or
alleged omission to state a material fact has been made by, or relates to,
information supplied by such party, and the parties’ relative intent,
knowledge, access to information and opportunity to correct or prevent such
statement or omission.  The parties
hereto agree that it would not be just and equitable if contributions pursuant
to this paragraph were to be determined by pro rata allocation or by any other
method of allocation which does not take account of the equitable
considerations referred to in the first sentence of this paragraph.  The amount paid by an indemnified party as a
result of the Losses referred to in the first sentence of this paragraph shall
be deemed to include any legal and other expenses reasonably incurred by such
indemnified party in connection with investigating or defending any Loss which
is the subject of this paragraph. No person guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the
Securities Act) shall be entitled to contribution from any Person who is not
guilty of such fraudulent misrepresentation.


 


(e)           Other
Indemnification.  The provisions of
this Section 2.08 shall be in addition to any other rights to
indemnification or contribution which an indemnified party may have pursuant to
law, equity, contract or otherwise.


 


11




















 


Section 2.09           Rule 144.


 


(a)           Rule 144 Reporting.  With a view to making available the benefits
of certain rules and regulations of the Commission that may permit the
sale of the Registrable Securities to the public without registration, MarkWest
shall:


 


(i)            make and keep public information
regarding MarkWest available, as those terms are understood and defined in Rule 144
under the Securities Act, at all times from and after the date hereof;


 


(ii)           file with the Commission in a timely
manner all reports and other documents required of MarkWest under the
Securities Act and the Exchange Act at all times from and after the date
hereof;


 


(iii)          so long as a Holder owns any
Registrable Securities, furnish to such Holder forthwith upon request a copy of
the most recent annual or quarterly report of MarkWest, and such other reports
and documents so filed as such Holder may reasonably request in availing itself
of any rule or regulation of the Commission allowing such Holder to sell
any such securities without registration; and


 


(iv)          take such additional actions as may be
reasonably required to permit the sale of the Registrable Securities pursuant
to Rule 144 as a result of subsequent amendments or modifications thereto.


 


(b)           Failure to Timely File Required
Documents with the Commission.


 


(i)            If MarkWest fails for any reason to
comply with the provisions of Section 2.09(a) during the period
beginning on the date which is six months from the date hereof and ending one
year from the date hereof, then MarkWest shall pay each Holder an amount equal
to the Liquidated Damages Amount for those days in excess of ten days in the
aggregate on which such Holder is unable to sell its Purchased Units pursuant
to Rule 144 under the Securities Act as a result of such failure to comply
with Section 2.09(a).  Any such
amounts shall be paid as liquidated damages and not as a penalty.


 


(ii)           The Liquidated Damages Amount shall
accrue on a daily basis and shall be paid to each Holder within five Business
Days of end of the month in which it accrues. 
Any payments made pursuant to this Section 2.09(b) shall
constitute the Holders’ exclusive remedy for such events.  The Liquidated Damages Amount imposed
hereunder shall be made to the Holders in immediately available funds.


 


Section 2.10           Transfer
or Assignment of Registration Rights. 
The rights granted to the Holders by MarkWest under this Article II
may be transferred or assigned by one or more Holders to one or more transferee(s) or
assignee(s) of such Registrable Securities, provided that (a) unless
such transferee is a Holder or an Affiliate of the transferring Holder, or the
transfer is to a swap counterparty, following such transfer or assignment, each
such transferee or assignee owns Registrable Securities representing at least
ten million dollars ($10,000,000) of Registrable Securities (determined by
multiplying the number of Registrable Securities owned by the average of the
closing price for Common Units for the ten (10) trading days preceding the
date of 


 


12

















 


such
transfer or assignment) or MarkWest otherwise consents to such transfer or
assignment, (b) MarkWest is given written notice prior to any said
transfer or assignment, stating the name and address of each such transferee
and identifying the securities with respect to which such registration rights
are being transferred or assigned, and (c) each such transferee assumes in
writing responsibility for its portion of the obligations of such Holder under
this Agreement (unless it is already a party to this Agreement).


 


Section 2.11           Limitation
on Subsequent Registration Rights. 
From and after the date hereof, MarkWest shall not, without the prior
written consent of the Holders of 66 2/3% of the outstanding Registrable
Securities, enter into any agreement with any current or future holder of any
securities of MarkWest that would allow such current or future holder to
require MarkWest to include securities in any Registration Statement filed by
MarkWest on a basis other than pari passu with, or subject to priority in favor
of, the Purchasers hereunder, except as contemplated under the Hydrocarbon
Purchase Agreement.


 


Section 2.12           Registration.  Any Registration Statement contemplated by
this Agreement when declared effective (including the documents incorporated
therein by reference) will comply as to form with all applicable requirements
of the Securities Act and the Exchange Act and will not contain an untrue
statement of a material fact or omit to state a material fact required to be stated
therein or necessary to make the statements therein not misleading.


 


ARTICLE III

MISCELLANEOUS


 


Section 3.01           Communications.  All notices and other
communications provided for or permitted hereunder shall be made in writing by
facsimile, internet electronic mail, courier service or personal delivery:


 


(a)           if to the
Purchasers, at the most current addresses given by the Purchasers to MarkWest
in accordance with the provisions of this Section 3.01, which addresses
initially are, with respect to the Purchasers, the addresses set forth in the
Purchase Agreement,


 


(b)           if to a transferee
of the Purchaser, to such Holder at the address provided pursuant to Section 2.10
above, and


 


(c)           if to MarkWest, at 1515 Arapahoe,
Tower 2, Suite 700, Denver, Colorado 80202, notice of which is given in
accordance with the provisions of this Section 3.01.


 


                All such notices and communications shall be deemed
to have been received at the time delivered by hand, if personally delivered;
when receipt acknowledged, if sent via facsimile or sent via Internet
electronic mail; and when actually received, if sent by courier service or any
other means.


 


Section 3.02           Successor
and Assigns.  This Agreement shall
inure to the benefit of and be binding upon the successors and assigns of each
of the parties, including subsequent Holders of Registrable Securities to the
extent permitted herein.


 


13

















 


Section 3.03           Assignment
of Rights.  All or any portion of the
rights and obligations of the Purchasers under this Agreement may be
transferred or assigned by the Purchasers in accordance with Section 2.10
hereof.


 


Section 3.04           Recapitalization,
Exchanges, etc. Affecting the Common Units. 
The provisions of this Agreement shall apply to the full extent set
forth herein with respect to any and all units of MarkWest or any successor or
assign of MarkWest (whether by merger, consolidation, sale of assets or
otherwise) which may be issued in respect of, in exchange for or in
substitution of, the Registrable Securities, and shall be appropriately
adjusted for combinations, recapitalizations and the like occurring after the
date of this Agreement.


 


Section 3.05           Specific
Performance.  Damages in the event of
breach of this Agreement by a party hereto may be difficult, if not impossible,
to ascertain, and it is therefore agreed that each such Person, in addition to
and without limiting any other remedy or right it may have, will have the right
to an injunction or other equitable relief in any court of competent jurisdiction,
enjoining any such breach, and enforcing specifically the terms and provisions
hereof, and each of the parties hereto hereby waives any and all defenses it
may have on the ground of lack of jurisdiction or competence of the court to
grant such an injunction or other equitable relief.  The existence of this right will not preclude
any such Person from pursuing any other rights and remedies at law or in equity
which such Person may have.


 


Section 3.06           Counterparts.  This Agreement may be executed in any number
of counterparts and by different parties hereto in separate counterparts, each
of which counterparts, when so executed and delivered, shall be deemed to be an
original and all of which counterparts, taken together, shall constitute but
one and the same Agreement.


 


Section 3.07           Headings.  The headings in this Agreement are for
convenience of reference only and shall not limit or otherwise affect the
meaning hereof.


 


Section 3.08           Governing
Law.  The laws of the State of
Delaware shall govern this Agreement without regard to principles of conflict
of laws.


 


Section 3.09           Severability
of Provisions.  Any provision of this
Agreement which is prohibited or unenforceable in any jurisdiction shall, as to
such jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions hereof or
affecting or impairing the validity or enforceability of such provision in any
other jurisdiction.


 


Section 3.10           Entire
Agreement.  This Agreement is
intended by the parties as a final expression of their agreement and intended
to be a complete and exclusive statement of the agreement and understanding of
the parties hereto in respect of the subject matter contained herein.  There are no restrictions, promises, warranties
or undertakings, other than those set forth or referred to herein with respect
to the rights granted by MarkWest set forth herein.  This Agreement supersedes all prior
agreements and understandings between the parties with respect to such subject
matter.


 


Section 3.11           Amendment.  This Agreement may be amended only by means
of a written amendment signed by MarkWest and the Holders of a majority of the
then outstanding 


 


14

















 


Registrable
Securities; provided,  however, that no such amendment shall
materially and adversely affect the rights of any Holder hereunder without the
consent of such Holder.


 


Section 3.12           No
Presumption.  In
the event any claim is made by a party relating to any conflict, omission, or
ambiguity in this Agreement, no presumption or burden of proof or persuasion
shall be implied by virtue of the fact that this Agreement was prepared by or
at the request of a particular party or its counsel.


 


Section 3.13           Aggregation
of Registrable Securities.  All
Registrable Securities held or acquired by any Persons who are Affiliates of
one another shall be aggregated together for the purpose of determining the
availability of any rights under this Agreement.


 


[The remainder of this page  is intentionally left blank.]


 


15

















 


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


 


	
  MARKWEST ENERGY PARTNERS, L.P.

  
	
   

  	
   

  	
   

  
	
  By:

  	
  MarkWest Energy GP, L.L.C.,

  
	
   

  	
  its general partner

  
	
   

  	
   

  	
   

  
	
  By:

  	
  /s/ NANCY K. BUESE

  
	
   

  	
  Name: 

  	
  Nancy K. Buese

  
	
   

  	
  Title:

  	
  SVP & Chief Financial Officer

  
				



 

















 


	
  MAGNETAR SPECTRUM FUND

  
	
   

  	
   

  	
   

  	
   

  
	
  By:

  	
  Magnetar
  Financial LLC,

  
	
   

  	
  its
  investment manager

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ PAUL SMITH

  
	
   

  	
   

  	
  Name: 

  	
  Paul Smith

  
	
   

  	
   

  	
  Title:

  	
  General Counsel

  
						



 

















 


	
  KAYNE
  ANDERSON MLP FUND, LP

  
	
   

  	
   

  	
   

  
	
  By:

  	
  Kayne
  Anderson Capital Advisors, L.P.,

  
	
   

  	
  its
  general partner

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ DAVID SHLADOVSKY

  
	
   

  	
   

  	
  David
  Shladovsky

  
	
   

  	
   

  	
  General Counsel

  
				



 


 


	
  KAYNE
  ANDERSON CAPITAL INCOME PARTNERS (QP), LP

  
	
   

  	
   

  	
   

  
	
  By:

  	
  Kayne
  Anderson Capital Advisors, L.P.,

  
	
   

  	
  its
  general partner

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ DAVID SHLADOVSKY

  
	
   

  	
   

  	
  David
  Shladovsky

  
	
   

  	
   

  	
  General Counsel

  
				



 


 


	
  KAYNE
  ANDERSON MIDSTREAM OPPORTUNITY FUND, LP

  
	
   

  	
   

  	
   

  
	
  By:

  	
  Kayne
  Anderson Capital Advisors, L.P.,

  
	
   

  	
  its
  general partner

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ DAVID SHLADOVSKY

  
	
   

  	
   

  	
  David
  Shladovsky

  
	
   

  	
   

  	
  General Counsel

  
				



 


 


	
  ARBCO
  II, L.P.

  	 

	
   

  	
   

  	
   

  
	
  By:

  	
  Kayne
  Anderson Capital Advisors, L.P.,

  	 

	
   

  	
  its
  general partner

  	 

	
   

  	
   

  	
   

  	 

	
   

  	
  By:

  	
  /s/ DAVID SHLADOVSKY

  	 

	
   

  	
   

  	
  David
  Shladovsky

  	 

	
   

  	
   

  	
  General Counsel

  	 

					



 

















 


	
  KAYNE ANDERSON ENERGY TOTAL RETURN FUND, INC.

  
	
   

  	
   

  
	
  By:

  	
  /s/ JAMES C. BAKER

  
	
   

  	
  James C. Baker

  
	
   

  	
  Vice President

  



 

















 


	
  TORTOISE
  ENERGY CAPITAL CORPORATION

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/
  DAVID J. SCHULTE

  
	
   

  	
  Name:

  	
  David
  J. Schulte

  
	
   

  	
  Title:

  	
  Chief Executive Officer

  



 

















 


	
  HARTZ
  CAPITAL INVESTMENTS, LLC

  
	
   

  	
   

  	
   

  
	
  By:

  	
  Hartz Capital, Inc.

  
	
   

  	
  its
  manager

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
  /s/ RONALD J. BANGS

  
	
   

  	
   

  	
  Ronald J. Bangs

  
	
   

  	
   

  	
  Chief Operating Officer

  
				



 

















 


Schedule A


 


	
  Purchaser

  	
   

  	
  Units Purchased

  	
   

  	
  Total Purchase

  Price

  	
   

  
	
  Magnetar Spectrum Fund

  	
   

  	
  1,904,762

  	
   

  	
  $

  	
  60,000,003.00

  	
   

  
	
  Kayne Anderson Capital
  Income Partners (QP), LP

  	
   

  	
  19,842

  	
   

  	
  625,023.00

  	
   

  
	
  Kayne Anderson MLP Fund,
  LP

  	
   

  	
  109,127

  	
   

  	
  3,437,500.50

  	
   

  
	
  Kayne Anderson Midstream
  Opportunity Fund, LP

  	
   

  	
  19,842

  	
   

  	
  625,023.00

  	
   

  
	
  ARBCO II, L.P.

  	
   

  	
  9,921

  	
   

  	
  312,511.50

  	
   

  
	
  Kayne Anderson Energy
  Total Return Fund, Inc.

  	
   

  	
  158,731

  	
   

  	
  5,000,026.50

  	
   

  
	
  Tortoise Energy Capital
  Corporation

  	
   

  	
  317,461

  	
   

  	
  10,000,021.50

  	
   

  
	
  Hartz Capital Investments,
  LLC

  	
   

  	
  317,461

  	
   

  	
  10,000,021.50

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Total

  	
   

  	
  2,857,147

  	
   

  	
  $

  	
  90,000,130.50