EXHIBIT 10.1


FIRST AMENDMENT TO

CERTAIN OPERATIVE AGREEMENTS


THIS FIRST AMENDMENT TO
CERTAIN OPERATIVE AGREEMENTS (this “Amendment”),
dated as of May 16, 2006, is by and among UNITED THERAPEUTICS CORPORATION,
a Delaware corporation (the “Lessee” or the “Construction Agent”); WACHOVIA DEVELOPMENT CORPORATION, a
North Carolina corporation (the “Borrower” or
the “Lessor”); the various banks and other
financial institutions which are parties hereto from time to time as holders of
the Credit Notes (subject to the definition of Credit Lenders in Appendix A to the Participation Agreement (hereinafter
defined), individually, a “Credit Lender”
and collectively, the “Credit Lenders”);
the various banks and other financial institutions which are parties hereto
from time to time as holders of the Mortgage Notes (subject to the definition
of Mortgage Lenders in Appendix A
to the Participation Agreement, individually, a “Mortgage
Lender” and collectively, the “Mortgage Lenders”;
each Credit Lender, each Mortgage Lender and the Lessor may be referred to,
individually, as a “Primary Financing Party”
and collectively, as the “Primary Financing Parties”);
and WACHOVIA BANK, NATIONAL ASSOCIATION, a national banking association, as the
agent for the Primary Financing Parties and, respecting the Security Documents,
as the agent for the Secured Parties (in such capacity, the “Agent”). Capitalized terms used but not otherwise defined in
this Amendment shall have the meanings set forth in Appendix A
to the Participation Agreement, and the rules of usage set forth in Appendix A to the Participation Agreement shall apply
herein.


W I T N E S S E T H


WHEREAS, the parties to this Amendment are parties to
that certain Participation Agreement dated as of June 28, 2004 (as
amended, modified, supplemented or restated from time to time, the “Participation Agreement”).


WHEREAS, the parties to this Amendment have agreed to
the amendments set forth herein, subject to terms and conditions set forth
herein.


NOW, THEREFORE, in
consideration of the agreements hereinafter set forth, and for other good and
valuable consideration, the receipt and adequacy of which are hereby
acknowledged, the parties hereto agree as follows:


ARTICLE I

AMENDMENTS TO PARTICIPATION AGREEMENT


1.1   Funding for Punch List Items.   Section 5.21
of the Participation Agreement is hereby added to read as follows:


5.21   Funding
for Punch List Items.


Prior to the submission by the Construction Agent of
the Officer’s Certificate referenced in Section 5.5 regarding Completion
of the Property, the Construction Agent shall submit a Requisition for a
Construction Advance to cover all anticipated punch list items necessary for
Final Completion of the Property. To the extent the conditions precedent set
forth in Section 5.4 are satisfied or waived and prior to the termination
of the Lender Commitments and the Lessor Commitments for the Property, the
above-described Construction Advance shall be funded in accordance with
the terms of the Operative Agreements into an account or accounts designated by
the Lessee (the “Punch List Account”).


Thereafter, the Lessee covenants and agrees that the
Lessee (a) shall maintain the amounts advanced into the Punch List Account
in Dollars only, (b) shall use the amounts advanced into the Punch List
Account only for punch list items in connection with the Property and (b) shall
provide to the Agent an itemized written accounting (pursuant to documentation
which is reasonably satisfactory 











to the Agent and until the
punch list items in connection with the Property have been fully paid) on or
prior to the tenth day of each month detailing the manner in which amounts in
the Punch List Account have been expended.


All amounts so advanced to the Lessee pursuant to this
Section 5.21 from time to time shall constitute Advances for purposes of
determining the Property Cost from the date of such Advance by the Lenders and
the Lessor.


Upon the occurrence of Final Completion of the
Property, the Construction Agent shall promptly (and in any event within 15
days) deliver an Officer’s Certificate to the Agent specifying (a) the
date as of which Final Completion occurred and (b) whether any amount
originally funded into the Punch List Account is remaining at such time. Any
such amount remaining after Final Completion shall be promptly paid to the
Agent for application pursuant to Section 8.7(b)(i) as a partial
payment of the outstanding amounts owing to the parties identified in such Section 8.7(b)(i).


1.2   Adjustment
of Waterfall regarding Unutilized Amounts in the Punch List Account.   Section 8.7(b)(i) of
the Participation Agreement is hereby deleted in its entirety and replaced by
the following:


(i)    Any such
payment or amount identified as or deemed to be Basic Rent, any amount in
respect of any Casualty, Condemnation or Environmental Violation pursuant to
Sections 15.1(a), 15.1(g) or 15.2 of the Lease (excluding any payments in
respect thereof which are payable to the Lessee in accordance with the Lease), any
amount (in connection with the exercise of remedies pursuant to the Security
Documents, the Agency Agreement, the Lease or otherwise) equal to any payment
identified as proceeds of the sale or other disposition or lease to a third
party of the Property or any portion thereof, any payment in respect of excess
wear and tear pursuant to Section 22.3 of the Lease, any payment pursuant
to Section 22.1(b) of the Lease (or otherwise) of the Maximum
Residual Guarantee Amount (or any such lesser amount as may be required by Section 22.1(b) of
the Lease), any payment of Termination Value, any other amount pursuant to the
Operative Agreements received by the Agent or otherwise received on behalf of
any Financing Party in connection with the exercise of rights and/or remedies
pursuant to any of the Security Documents, the Agency Agreement, the Lease or
otherwise in connection with the occurrence of any Event of Default, the amount
(if any) remaining in the Punch List Account after the date of Final Completion
as described in Section 5.21 and any other amount received by the Agent or
the Lessor not otherwise referenced in this Section 8.7, as the case may
be, shall be applied and allocated by the Agent:


first, to the Primary Financing
Parties for application and allocation to any and all amounts owing under the
Operative Agreements to the Primary Financing Parties in accordance with the
terms and provisions of the Intercreditor Agreement; and


second, any excess shall be paid
to the Lessee or such Person or Persons as the Lessee may designate.


1.3   Amended Definitions.   The
definition of “Final Completion” in Appendix A
to the Participation Agreement is hereby deleted and replaced in its entirety
by the following:


“Final Completion” shall mean, with respect to the
Property, such time as the acquisition, installation, testing and final
completion of the Improvements on the Property has been achieved in accordance
with the Plans and Specifications, the Agency Agreement and/or the Lease, and
in compliance with all Legal Requirements and Insurance Requirements and a
certificate of occupancy has been issued with respect to the Property by the
appropriate governmental entity (except if non-compliance, individually
or in the aggregate, shall not have and could not reasonably be expected to
have a Material Adverse Effect or if compliance with any of the foregoing is
otherwise waived by the Agent upon instruction from the Secured Parties).



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1.4   Additional Definition.   The
Definition for the following term shall be added in appropriate alphabetical
order in Appendix A to the Participation
Agreement as follows:


“Punch List Account” shall
have the meaning given to such term in Section 5.21 of the Participation
Agreement.


ARTICLE II

AMENDMENTS TO INTERCREDITOR AGREEMENT


2.1   Adjustment
of Waterfall regarding Unutilized Amounts in the Punch List Account.   Section 4.3(a)(iv) of
the Intercreditor Agreement is hereby deleted in its entirety and replaced by
the following:


(iv)  An amount equal to (A) any payment
pursuant to Section 22.1(b) of the Lease (or otherwise) of the Maximum
Residual Guarantee Amount (or any such lesser amount as may be required by Section 22.1(b) of
the Lease), (B) any other amount payable after the occurrence of an Event
of Default not covered by Sections 4.3(a)(i) or 4.3(a)(iii) above
(including without limitation any amount received in connection with an action
for liquidated damages pursuant to Section 17.4 or Section 17.6 of
the Lease or by setoff by the Agent), (C) any payment of Termination Value
not otherwise subject to Section 4.3(a), (D) any other amount payable
pursuant to the exercise of rights and/or remedies pursuant to the Security
Documents not otherwise subject to Section 4.3(a) and (E) the
amount (if any) remaining in the Punch List Account after the date of Final
Completion as described in Section 5.21 of the Participation Agreement
shall be applied and allocated by the Agent first, ratably,
to the payment of the principal and interest balance of the Credit Loans then
outstanding, second, to any and all other
amounts owing under the Operative Agreements to the Credit Lenders under the
Credit Loans, third, to the extent such amount
exceeds the maximum amount to be retained pursuant to the foregoing provisions
of this paragraph (iv), ratably to the payment of the principal and interest
balance of the Mortgage Loans then outstanding, fourth,
to any and all other amounts owing under the Operative Agreements to the
Mortgage Lenders under the Mortgage Loans, fifth, to the
payment to the Lessor of the outstanding principal balance of all Lessor Advances
plus all outstanding Lessor Yield with respect to such outstanding Lessor
Advances, sixth, to any and all other amounts
owing under the Operative Agreements to the Lessor, and seventh,
to the extent moneys remain after application and allocation pursuant to
clauses first through sixth
above, to any and all other amounts owing to any Financing Party as the Lessor
shall determine.


ARTICLE III

CONDITIONS TO EFFECTIVENESS


3.1   Closing Conditions.


This Amendment shall become effective as of the date
hereof upon satisfaction of the following conditions (in form and substance
reasonably acceptable to the Agent):


(a)   Executed Amendment.   The
Agent shall have received a copy of this Amendment duly executed by the
Borrower, the Agent, the Majority Secured Parties and the Lessee.


(b)   Other.   The
Agent shall have received such other documents, agreements or information which
it may reasonably request relating to the Lessee and the transactions
contemplated by this Amendment and any other matters relevant hereto and
thereto, all in form and substance satisfactory to the Agent in its sole good
faith discretion.



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ARTICLE IV

MISCELLANEOUS


4.1   Amended Terms.   All
references to the Participation Agreement in each of the Operative Agreements
shall hereafter mean the Participation Agreement as amended by this Amendment. Except
as specifically amended hereby or otherwise agreed, the Operative Agreements
are hereby ratified and confirmed and shall remain in full force and effect
according to their respective terms.


4.2   Representations
and Warranties of the Lessee.   The Lessee represents and
warrants as follows as of the date hereof:


(a)    It has
taken all necessary action to authorize the execution, delivery and performance
of this Amendment.


(b)   This
Amendment has been duly executed and delivered by the Lessee and constitutes
the Lessee’s valid and legally binding obligation, enforceable in accordance
with its terms, except as such enforceability may be subject to (i) bankruptcy,
insolvency, reorganization, fraudulent conveyance or transfer, moratorium or
similar laws affecting creditors’ rights generally and (ii) general
principles of equity (regardless of whether such enforceability is considered
in a proceeding at law or in equity).


(c)    No
consent, approval, authorization or order of, or filing, registration or
qualification with, any Governmental Authority or third party is required in
connection with the execution, delivery or performance by the Lessee of this
Amendment, except any filing required to be made by the Lessee pursuant to the
Securities Exchange Act of 1934, as amended, as a result of this Amendment.


(d)   The
representations and warranties set forth in Section 6.2 of the
Participation Agreement are true and correct in all material respects as of the
date hereof (except for those which expressly relate to an earlier date).


4.3   Operative Agreement.   This
Amendment shall constitute an Operative Agreement under the terms of the
Participation Agreement.


4.4   Entirety.   This
Amendment and the other Operative Agreements embody the entire agreement
between the parties hereto and supersede all prior agreements and
understandings, oral or written, if any, relating to the subject matter hereof.


4.5   Counterparts; Telecopy.   This
Amendment may be executed in any number of counterparts, each of which when so
executed and delivered shall be an original, but all of which shall constitute
one and the same instrument. Delivery of an executed counterpart to this
Amendment by telecopy shall be effective as an original and shall constitute a
representation that an original will be delivered.


4.6   GOVERNING LAW.   THIS
AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES UNDER THIS AMENDMENT
SHALL BE GOVERNED BY AND CONSTRUED, INTERPRETED AND ENFORCED IN ACCORDANCE WITH
THE INTERNAL LAWS OF THE STATE OF NEW YORK (WITHOUT GIVING EFFECT TO THE
PRINCIPALS THEREOF RELATING TO CONFLICTS OF LAW), EXCEPT TO THE EXTENT THE LAWS
OF THE STATE WHERE THE PROPERTY IS LOCATED ARE REQUIRED TO APPLY.


4.7   Submission to Jurisdiction; Service
of Process; Waiver of Jury Trial; Venue, Etc.   The
jurisdiction, service of process, waiver of jury trial, venue and other
provisions set forth in Section 12.7 of the Participation Agreement are
hereby incorporated by reference, mutatis mutandis.


4.8   Fees.   The Lessee
agrees to pay all reasonable fees and expenses of the Agent in connection with
the preparation, execution and delivery of this Amendment, including, without
limitation, the reasonable fees and expenses of Moore & Van Allen
PLLC.


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IN
WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly
executed on the date first above written.




	
  THE CONSTRUCTION AGENT

  	
   

  	
   

  	
   

  	
   

  
	
  AND THE LESSEE:

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  UNITED THERAPEUTICS CORPORATION

  
	
   

  	
   

  	
  By:

  	
   

  	
  /s/ FRED T. HADEED

  
	
   

  	
   

  	
  Name:

  	
   

  	
  Fred T. Hadeed

  
	
   

  	
   

  	
  Title:

  	
   

  	
  EVP Business Development & CFO

  






 


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  THE BORROWER AND THE LESSOR:

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  WACHOVIA DEVELOPMENT CORPORATION

  
	
   

  	
   

  	
  By:

  	
   

  	
  /s/ EVANDER S.
  JONES, Jr.

  
	
   

  	
   

  	
  Name:

  	
   

  	
  Evander S. Jones, Jr.

  
	
   

  	
   

  	
  Title:

  	
   

  	
  Director

  






 


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  CREDIT LENDER:

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  WACHOVIA BANK, NATIONAL ASSOCIATION

  
	
   

  	
   

  	
  By:

  	
   

  	
  /s/ J. KENT TOMPSON

  
	
   

  	
   

  	
  Name:

  	
   

  	
  J. Kent Tompson

  
	
   

  	
   

  	
  Title:

  	
   

  	
  Senior Vice President

  






 


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  MORTGAGE LENDER:

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  WACHOVIA BANK, NATIONAL ASSOCIATION

  
	
   

  	
   

  	
  By:

  	
   

  	
  /s/
  J. Kent Tompson

  
	
   

  	
   

  	
  Name:

  	
   

  	
  J. Kent Tompson

  
	
   

  	
   

  	
  Title:

  	
   

  	
  Senior Vice President

  






 


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In addition, provisions in our license and assignment
agreements impose other restrictions on our freedom to develop and market our
products. For example, in assigning Remodulin to us, GlaxoSmithKline retained
an exclusive option and right of first refusal to negotiate a license agreement
with us if we ever decide to license any aspect of the commercialization of
Remodulin anywhere in the world. Similarly, in connection with its licenses of
beraprost to us, Toray Industries, Inc. obtained a right of first refusal
from us to develop and sell in Japan up to two compounds that we develop. We
also agreed to provisions giving Toray the conditional right to approve our
North American distributor, establishing a conditional restricted
non-competition clause, and requiring minimum annual sales in order to maintain
our exclusive rights to beraprost. The restrictions that we have accepted in
our license and assignment agreements restrict our freedom to develop and
market our products in the future.











 




	
  

  	
   

  	
   

  	
   

  	
   

  
	
  THE AGENT:

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  WACHOVIA BANK, NATIONAL ASSOCIATION

  
	
   

  	
   

  	
  By:

  	
   

  	
  /s/ EVANDER S. JONES,
  JR.

  
	
   

  	
   

  	
  Name:

  	
   

  	
  Evander S. Jones, Jr.

  
	
   

  	
   

  	
  Title:

  	
   

  	
  Director

  






 


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