Document:

EXHIBIT 10.35

PATENT LICENSE AND SETTLEMENT
AGREEMENT

This Patent
License and Settlement Agreement (“Agreement”), dated and effective as
described herein, is made and entered into by and between FORGENT NETWORKS,
INC. (“Forgent”) and its wholly-owned subsidiary, COMPRESSION LABS, INC. (“CLI”),
each a corporation having its principal office and place of business at 108
Wild Basin Rd., Austin, TX 78746 (hereinafter jointly referred to as “Grantor”)
and the parties listed on Exhibit A hereto (hereinafter referred to
separately as “Grantee” or collectively as “Grantees”), acting severally on
behalf of themselves and in the interest of their respective Subsidiaries.  Each Grantee and each of such Grantee’s
Subsidiaries are hereinafter singularly and collectively referred to as “Licensee”;
and each of Grantor and Licensee are referred to, singularly, as a “Party” and
collectively, as “Parties”.

WHEREAS, the
following lawsuits have been commenced by the Parties relating to United States
Patent No. 4,698,672 which have been either consolidated in the United States
District Court for the Northern District of California (“ND Calif.”) for
pretrial purposes, as set forth in the Multidistrict Litigation Panel Order
dated February 16, 2005 (“In Re Compression Labs,
Inc. Patent Litigation, MDL No. M:05cv01654”), or were originally
filed in the ND Calif.:

Compression
Labs, Inc. v. Agfa Corp. et al., 2:04-CV-158
(E.D. Tex.) (“the Agfa case:);

Compression
Labs, Inc. v. Dell Inc., et al., 2:04-CV-159
(E.D. Tex.) (“the Dell case”);

Compression Labs, Inc. v. Acer America Corp. et
al., 2:04-CV-294 (E.D. Tex.) (“the Acer case”);

Compression
Labs, Inc. v. Creo, Inc., et al., 2:04-CV-410
(E.D. Tex.) (the “Creo case”);

Agfa
Corp. et al. v. Compression Labs, Inc., et al., C.A.
No. 04-818 (D. Del.);

Yahoo!
Inc. v. Compression Labs, Inc., et al.,
C.A. No. 07-918 (D. Del.);

Audiovox
Corp. et al. Compression Labs, Inc., et al.,
No. 04-1293 (D. Del.);

Sun
Microsystems, Inc. v. Compression Labs, Inc.
Case No. 5:04-CV-3124 (N.D. Cal.);

Google
Inc. v. Compression Labs, Inc. et al.
Case No. 04-CV-3934 (N.D. Cal.); and

Microsoft
Corporation v. Compression Labs, Inc. et al.,
Case No. 05-CV-01567 (N.D. Cal.) (hereinafter each a “Lawsuit” or “MDL Action”;
and collectively the “Lawsuits” or “MDL Actions”).

WHEREAS, the
Parties now desire to avoid further litigation risks and expenses, and Grantor
and each Grantee mutually seek a settlement of the Lawsuits to which Grantor
and such Grantee, and/or one or more of such Grantee’s Subsidiaries, are
parties and enter into this Agreement providing for a full, final, complete and
global settlement of the subject matter of such Lawsuit, and for certain
releases, licenses and covenants not to sue, all on the terms and conditions
set forth herein.

NOW, THEREFORE,
in consideration of the above premises and the mutual covenants and obligations
herein and other good and valuable consideration, the Parties hereby agree as
follows:

 

Article 1. — Definitions

In this Agreement, the following terms
shall have the respective meanings set forth below:

1.1           “Commercial
Activities”, “Commercialization”, or the act of “Commercializing”, or any
derivative of such terms, mean, with respect to any product or service, to
make, have made, sell, have sold, offer for sale, rent, offer to rent,
rent-to-own, lease or license, offer under a license, offer, provide, use, have
used, import, export, use or permit the use, sale, offer for sale, lease,
import or export, or otherwise deal in, transfer or dispose of, or permit the
transfer or disposition of, any product or service, either directly to any
entity (including any Subsidiary or any other entity for whom or for whose
account any such product or service is Commercialized), or directly or
indirectly to Permitted Agents and Customers.

1.2           “Effective
Date” means the date on which the last Grantee transmits a fully executed copy
of this Agreement to Grantor in accordance with § 3.1.

1.3           “Infringement”
means any infringement, whether direct or indirect (including contributory
and/or by inducement), known or unknown, that was, could have been, or could be
alleged with respect to the Licensed Patents, including but not limited to the
provisions of 35 U.S.C. § 271.

1.4           “Licensed
Fields” means all fields of use.

1.5           “Licensed
Patents” means United States Patent No. 4,698,672 and any reissues,
reexaminations, renewals or extensions (including any supplementary protection
certificates), continuations, continuations-in-part and divisions thereof,
confirmation patents or registration patents or patents of addition based
thereon, and any and all foreign counterpart patents (including utility
models), including without limitation those listed on Exhibit B.

1.6           “Permitted
Agents and Customers” means, with respect to each Grantee and its Subsidiaries,
such entity’s (whether direct or indirect, immediate or remote, thereof)
customers, end-users, licensees, original equipment manufacturers and private
label manufacturers, retail and wholesale distributors, sales representatives,
resellers, dealers, application software providers, independent software
vendors, independent service or repair centers, suppliers, and the agents,
successors, and assigns of each of the foregoing and any and all entities with
whom or with which any such Grantee or its Subsidiaries seeks prospectively to
enter into any of the foregoing relationships.

1.7           “Product”
or “Products” means all devices, products (whether hardware, software, firmware
or any combination of hardware, software, firmware and/or services),
components, materials, and services, the Commercialization of which were, are,
or could be alleged to be covered by the Licensed Patents, including, without
limitation, those that implement the JPEG standard (including ISO/IEC IS 10918)
to compress (or decompress), store, copy, manipulate, distribute, display or
print digital data.

 2
 

 

1.8           “Released
Parties” shall mean with respect to each Grantee, such Grantee, such Grantee’s
Subsidiaries, any and all of its and their officers, directors, shareholders,
and such Grantee’s and its Subsidiaries’ Permitted Agents and Customers.

1.9           “Subsidiary”
or “Subsidiaries” means with respect to each Grantee any, current and/or
future, company, affiliate, division, enterprise or other business unit owned
or controlled either directly or indirectly by such Grantee, or under common
control with such Grantee, from time to time: (i) through ownership or control
of fifty percent (50%) or more of the voting stock or other voting interest in
such entity, provided, however, that in any country where such Grantee (or an
entity under common control with such Grantee) is or was not permitted by law
to own fifty percent (50%) or more of the voting stock or other voting interest
of a local entity, then such local entity shall be deemed a subsidiary of such
Grantee for purposes of this Agreement if such Grantee (or an entity under
common control with such Grantee) owns, directly or indirectly, the maximum
voting stock or other voting interest that it may own and if the business
activities of the local entity are substantially controlled, directly or
indirectly, by such Grantee (or an entity under common control with such
Grantee); (ii) in the case of a joint venture formed by such Grantee (or an
entity under common control with such Grantee) and an independent entity, through
ownership or control of fifty percent (50%) or more of the voting stock or
other voting interest in such joint venture, provided, however, that in any
country where such Grantee (or an entity under common control with such
Grantee) is or was not permitted by law to own fifty percent (50%) or more of
the voting stock or other voting interest of a local entity, then such local
entity shall be deemed a subsidiary of such Grantee for purposes of this
Agreement if such Grantee (or an entity under common control with such Grantee)
owns, directly or indirectly, the maximum voting stock or other voting interest
that it may own and if the business activities of the local company are
substantially controlled, directly or indirectly, by Grantee (or an entity under
common control with such Grantee); or (iii) through the power to exercise a
controlling influence over the management or policies of such entity whether
through ownership of securities, by contract, or otherwise.  Notwithstanding the foregoing, the Licensee
obligations imposed herein shall be obligations of Grantees.

1.10         “Term
of this Agreement” means the period commencing on the Effective Date of this
Agreement and continuing until expiration of the last to expire of the Licensed
Patents and all claims for damages under the Licensed Patents are barred by
law.

1.11         “Total
Payment” means the total sum of eight million dollars ($8,000,000.00) to be
received by Grantor if each and every Grantee makes the payment required to be
made by each such Grantee to Grantor in accordance with Section 4.1.  For avoidance of doubt, the actual payment to
Grantor, net of any withheld amounts for taxes, may be less as described in
Section 4.3.

1.12         “Unlicensed
Third Party” means a person or entity Commercializing a Product who does not
have a license or release to Commercialize such Product, whether granted
directly by Grantor or indirectly as one of the Permitted Agents and Customers.

 3
 

 

Article
2. — Warranties And Representations

2.1           Each
Grantor makes to each Licensee the following warranties and representations:

(a)           Each
Grantor has the exclusive right to grant rights, licenses, privileges, releases
and immunities under or relating to the Licensed Patents in the Licensed Fields
including the rights, licenses, privileges, releases and immunities granted
hereunder to such Licensee.

(b)           Each
Grantor has the right to enter into this Agreement with each Grantee.  Each Grantor has the power and authority to
enter into this Agreement, to perform all of its duties and obligations under
this Agreement and to grant all releases granted by such Grantor under this
Agreement.

(c)           There
are no liens, conveyances, mortgages, assignments, encumbrances or other
agreements which would prevent or impair the full and complete exercise of all
substantive rights, licenses, privileges, releases and immunities granted by
Grantor to each Licensee and such Licensee’s successors, assigns, and Permitted
Agents and Customers pursuant to the terms and conditions of this Agreement.

(d)           Neither
Grantor has entered into nor shall enter into any agreements which would
interfere with or derogate from the rights, licenses, privileges, releases and
immunities granted by it to each Licensee and such Licensee’s successors,
assigns, and Permitted Agents and Customers.

(e)           No
royalty or other fee or remuneration arising under the Licensed Patents is or
shall be due to any third party for the Commercialization of Products by each
Licensee or the manufacture or supply of Products for or to such Licensee.  This paragraph shall not waive, restrict or
otherwise limit the payment due to Grantor under Article 4 hereof.

(f)            There
are no patents or applications for same owned or controlled by Grantor, one or
more claims of which would be infringed by the use or practice of the rights,
privileges or immunities granted to such Grantee and such Licensee under this
Agreement.

(g)           Grantor
has no Japanese counterpart to any of the Licensed Patents.

(h)           Based
on Grantor’s inherent knowledge and awareness of its and its subsidiaries’ issued
patents and pending patent applications, Grantor has no knowledge of any claims
in any currently issued or pending patent anywhere in the world, other than the
Licensed Patents, that are currently owned or licensable by Grantor or any of
its Subsidiaries and that Grantor or any of its Subsidiaries believes or
suspects are or may be infringed by any products or services of the Grantees or
their subsidiaries.  For the avoidance of
doubt, nothing in this section shall be construed to encumber in any manner
whatsoever any patents, other than the Licensed Patents, that are currently
owned or licensable by Grantor or any of its Subsidiaries.  Furthermore, as per section 3.6, nothing in
this section applies to U.S. Pat. No. 6,285,746 B1

 4
 

 

(including
parents, continuations, continuations-in-part, divisions, renewals, extensions,
re-exams, and reissues related thereto), which the parties explicitly
agree is not subject to or affected by this Agreement in any manner whatsoever.

2.2           Each
Grantee, severally and not jointly, makes the following warranties and
representations:

(a)           Each
Grantee has the power and authority to enter into this Agreement and to perform
all of its duties and obligations under this Agreement.

Article 3. — Effective Date, Dismissal of Lawsuit,
Grant Of Licenses, Releases,

Non-Assertions Under The Licensed Patents, And No Admission

In consideration of the Payments to be
made by each Grantee specified in Section 4 hereof, and for other good and
valuable consideration:

3.1           This Agreement shall become effective only once all
parties have fully executed the Agreement. 
Specifically, this Agreement shall become effective as follows.  Grantor shall execute this Agreement and
transmit copies of this executed Agreement (in PDF format) via e-mail to all
counsel of record for Grantees on 5 October 2006.  In order for this Agreement to become
effective, all Grantees must transmit a fully executed copy (in PDF format) of
this Agreement to Grantor on or before 25 October 2006 at the following
e-mail address: tnagy@susmangodfrey.com. 
The date on which the last Grantee transmits a fully executed copy of
this Agreement to Grantor as described in this paragraph shall be the Effective
Date of this Agreement.  Grantor shall,
within 24 hours of the Effective Date send an e-mail notification to all
Grantees at the e-mail addresses mentioned above to inform Grantees that the
Agreement has become effective and specifically identifying the Effective Date
of this Agreement.

3.2           Within
five (5) business days of receipt of the payment from a Grantee of its Share as
specified in Section 4.1, each Grantor shall file a signed copy of a notice of
voluntary dismissal of any claims, counterclaims, and cross-claims filed in any
of the MDL Actions as to such Grantee (and/or its Subsidiaries, as
appropriate), with prejudice pursuant to FRCP 41(a)(1) in the form attached
hereto as Exhibit C.  This
Agreement comprises a full settlement of all claims of past and future patent
Infringement with respect to the Products as to such paid Grantee and its
Subsidiaries.  By filing notices of
voluntary dismissal of claims as to such Grantee (and/or its Subsidiaries,
direct or indirect, as appropriate) pursuant to FRCP 41(a)(1), each Grantor
hereby dismisses the aforementioned claims, counterclaims, and cross-claims
against such Grantee (and/or its Subsidiaries, as appropriate) with
prejudice.  Likewise, within five (5)
business days thereafter, each paid Grantee (and/or its Subsidiaries, as
appropriate) agrees to file a signed copy of a notice of voluntary dismissal
consistent with the form and content set forth in Exhibit C by such Grantee
(and/or its Subsidiaries, as appropriate) of claims, counterclaims, and
cross-claims filed in any of the MDL Actions against each Grantor pursuant to
FRCP 41(a)(1).

3.3           For
the term of this Agreement, Grantor hereby grants each Grantee and its
Subsidiaries a worldwide, non-exclusive, fully paid-up and irrevocable license,
privilege and immunity under all claims of the Licensed Patents,

 5
 

 

without the right to sublicense except as
specifically permitted in this paragraph and Section 9, to practice any
methods, processes, or procedures allegedly covered under any claim of the
Licensed Patents and further to Commercialize any and all Products (including
combinations incorporating such Products) in the Licensed Fields.  Grantor expressly agrees that such license
exhausts its rights in the Licensed Patents and that such license extends to
each Grantee’s and its Subsidiaries’ Permitted Agents and Customers to the
extent that such Permitted Agents and Customers Commercialize such Grantee’s or
its Subsidiaries’ Products (including combinations incorporating such
Products).  As may be necessary to effect
the foregoing sentence, each such Licensee shall have the right to grant
sublicenses to its Permitted Agents and Customers, retroactive to the Effective
Date of this Agreement.

3.4           Provided
that this Agreement becomes effective as set forth in Section 3.1 and that
Grantor receives from a Grantee the payment of such Grantee’s Share due Grantor
under Section 4.1 hereof, each Grantor, for itself and its successors and
assigns, hereby releases and discharges the Released Parties with respect to
such Grantee’s or its Subsidiaries’ Products (including combinations
incorporating such Products) from any and all actions, causes of action, claims
or demands whatsoever, in law or equity, resulting from the Infringement,
either past or future, of any claims of the Licensed Patents which Grantor had
or may have had prior to the Effective Date under the Licensed Patents.

3.5           Provided
that this Agreement becomes effective as set forth in Section 3.1 and that
Grantor receives from a Grantee the payment of such Grantee’s Share due Grantor
under Section 4.1 hereof, each Grantor further agrees for itself and its
successors and assigns that it will not, at any time or in any capacity, assert
any claim or commence or prosecute any action, suit or proceeding, or assist
any third party or affiliated party to assert any claim or commence or prosecute
any action, suit or proceeding, against any Released Parties with respect to
such Grantee’s or its Subsidiaries’ Products (including combinations
incorporating such Products) based in whole or in part on Infringement of the
Licensed Patents in the Licensed Fields. 
For the avoidance of uncertainty, Grantor expressly agrees that each
Grantee, its Subsidiaries, and its Permitted Agents and Customers may advocate,
advise, or suggest that Unlicensed Third Parties utilize the JPEG standard or
make any other alleged uses of the Licensed Patents.

3.6           Nothing
in this Agreement shall be construed to grant any Licensee any right:

(a)           to
license any Unlicensed Third Party to Commercialize any devices, products or
services that are not or do not incorporate Products of such Licensee under
this Agreement; and

(b)           under
the Licensed Patents, other than with respect to the Products in the Licensed
Field.

Notwithstanding anything else in this
Agreement, nothing in this Agreement shall be construed to apply to U.S. Pat.
No. 6,285,746 B1 (including parents,
continuations, continuations-in-part, divisions, renewals, extensions,
re-exams, and reissues related thereto) or to affect in any
manner whatsoever the claims or defenses at issue in Forgent
Networks, Inc., v. Echostar Technologies Corporation, et al., C.A.
No.: 6:06-CV-208 (E.D. Tex., Tyler Division).

 6
 

 

3.7           Grantees,
their Subsidiaries, Licensees, and the Released Parties reserve all claims and
defenses that they may have had in the Lawsuits.  Neither this Agreement, the dismissal of any
of the Lawsuits, nor any payment, license, release, covenant not to sue or
other transaction undertaken pursuant thereto or hereto, constitutes or shall
be construed as an admission by any Grantee, Licensee, or any Released Party
with respect to any claim or defense including but not limited to contentions
of Infringement or validity or enforceability of any Licensed Patent.

3.8           The
Parties acknowledge that Products include software products that are often
distributed to customers by providing a master copy of the software to a
distributor, reseller, original equipment manufacturer, value-added reseller,
or other third party authorized to reproduce and distribute the software,
either alone or as part of a larger product of the third party.  The releases, licenses, and covenants granted
in this Agreement shall apply to the reproduction and distribution by
authorized third parties of such software, either alone or as part of a larger
product of the third party, and nothing in this Agreement is intended to limit,
restrict or inhibit any Licensee or Released Party from using such master
copies.

3.9           Notwithstanding
Article 2, if Grantor does not have the right to grant fully the releases,
licenses, and covenants set out in this Agreement, in addition to any other
remedies Grantees might have, Grantor grants the broadest such rights it is
entitled to grant consistent with the terms set out herein.

3.10         All
rights under Section 1542 of the Civil Code of the State of California, and
under any and all similar laws of any governmental entity, are hereby expressly
waived. Each party is aware that said Section 1542 of the Civil Code provides
as follows:

“A
GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR DOES NOT KNOW OR
SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF EXECUTING THE RELEASE, WHICH IF
KNOWN BY HIM MUST HAVE MATERIALLY AFFECTED HIS SETTLEMENT WITH THE DEBTOR.”

3.11         The
Parties agree that this Agreement is in full and complete settlement of the
rights and obligations of the Grantor, on the one hand, and the Grantees and
their Subsidiaries, on the other hand, as between each other, in connection
with the Lawsuits.  From and after
payment by a Grantee of its Share, this Agreement may be pleaded as full and
complete defense by such Grantee, on behalf of itself and its Subsidiaries, and
by any Released Party of the Grantee, to any action, suit or claim and may be
used as an injunction against any such action, suit, claim, or other proceeding
of any type which may be prosecuted, initiated or attempted in violation of the
terms hereof.  Each Grantee, Subsidiary
and other Released Party shall be entitled to receive its attorneys’ fees and
other related legal expenses incurred in defending against any suit, action or
claim brought or attempted in violation of the terms of this Agreement.

3.12         Notwithstanding
the representations made by Grantor in 2.1(a), concurrently with the receipt by
Grantor of the last Grantee payment identified in Article 4, but in any event
not more than five (5) business days after such date, Grantor shall request
that General Instrument Corporation execute a release in the form attached
hereto as Exhibit E.  This request shall
be made pursuant to any and all rights Grantor has under its assignment from
General Instrument Corporation.  Upon
receipt of an executed copy of the release from General Instrument Corporation,
those Grantees

 7
 

 

with actions pending wherein General
Instrument Corporation is a party will execute and file a dismissal of General
Instruments in the form set forth in Exhibit C.

Article 4. — Payment

4.1           In
consideration for the rights, licenses, privileges, immunities, releases and
non-assertions set forth in Article 3 hereof and in reliance upon Grantor’s
warranties and representations set forth in Article 2 hereof, and for other
good and valuable consideration, each Grantee shall pay to Grantor the portion
of the Total Payment (such portion of the Total Payment being such Grantee’s “Share”)
set forth opposite the name of such Grantee in Exhibit D to this Agreement
and incorporated herein by reference. 
Unless Section 4.3 applies, each Grantee must complete payment of its
portion to Grantor within fourteen (14) days of the Effective Date of this
Agreement. Specifically, each Grantee must complete payment of its portion to
Grantor within fourteen (14) days of the date on which the Grantee receives
Grantor’s e-mail notification that the Agreement has become effective, as
described in Section 3.1.  No portion of
the Total Payment due Grantor under this Section 4.1 shall be refundable for
any reason whatsoever.  No Grantee shall
be liable for payment to Grantor of any other Grantee’s Share for any reason
whatsoever.

4.2           Each
Grantee shall make payment of its Share to Grantor, in care of Grantor, by
electronic transfer of funds, as follows:

JP
Morgan Chase Bank

700 Lavaca Street

Austin, TX 78701

ABA # 113000609

SWIFF
# TCBKUS44

TAX ID # 74-2415696

CREDIT TO
ACCOUNT: 09922767859

ACCOUNT NAME:
FORGENT NETWORKS, INC.

Forgent and CLI shall, as between
themselves, allocate amounts received under this Agreement as they see fit; no
Grantee shall have any obligation in that regard other than the payment of its
respective Share.

4.3           The
Grantees listed in Exhibit F represent that, due to the particular
nature of their organizations and due to obligations imposed upon them by their
respective foreign tax authorities, they are unable to pay their Shares within
the time frame set forth in Section 4.1. 
Accordingly, Grantor agrees to cooperate with each Grantee and to
complete and provide tax forms and other documents required by applicable tax
authorities necessary to avoid withholdings or deductions and/or to claim the
benefit of any favorable withholding rates under applicable treaties (“Necessary
Documents”), in a timely manner upon being supplied such documents by such
Grantee.  In turn, these Grantees agree
to take all necessary steps to obtain approval from the applicable tax
authorities as quickly as possible. 
These Grantees

 8
 

 

shall complete payment of their Share to
Grantor within thirty (30) days after receiving the Necessary Documents from
Grantor in a form acceptable to, and accepted by, the applicable tax authority.

Article 5. — Term

5.1           This
Agreement shall become effective as of its Effective Date and shall remain in
full force during the Term of this Agreement.

5.2           Surviving
any expiration or termination of this Agreement are (i) the obligations of
Grantor and Grantees delineated in Sections 3.3, 3.4, 3.5, 3.7, 3.8, 3.9, 3.10,
3.11, 4.1, 9, and 13; (ii) any cause of action or claim of Grantor or Grantees,
accrued, or to accrue, because of any breach or default by the other party
hereunder; and (iii) the provisions of Sections 1, 2, 5.2, 7 and 8.

5.3           As
between Grantor and any Grantee, this Agreement may only be terminated upon the
mutual written agreement of such Parties.

Article
6. — Disclaimer

Nothing in this Agreement is or shall be
construed as: (i) a warranty or representation by Grantor as to the validity,
scope or enforceability of the Licensed Patents; (ii) any warranty or
representation by Grantor that anything made, used, sold, licensed, offered for
sale, offered for license or otherwise disposed of under any license granted in
this Agreement is or will be free from Infringement of patents, copyrights, and
other rights of unaffiliated third parties; (iii) an obligation on the part of
Grantor to bring or prosecute actions or suits against third parties for
Infringement; or (iv) granting by implication, estoppel or otherwise any
licenses under patents owned by Grantor, other than the Licensed Patents.
EXCEPT AS EXPRESSLY SET FORTH IN THIS AGREEMENT, GRANTOR MAKES NO
REPRESENTATIONS AND EXTENDS NO WARRANTIES OF ANY KIND, EITHER EXPRESS OR
IMPLIED. THERE ARE NO EXPRESS OR IMPLIED WARRANTIES OF MERCHANTABILITY OR
FITNESS FOR A PARTICULAR PURPOSE, OR THAT PRODUCTS OR THE USE OF PRODUCTS WILL
NOT INFRINGE ANY UNAFFILIATED THIRD PARTY PATENT, COPYRIGHT, TRADEMARK OR OTHER
RIGHTS.  Any warranty made by any Grantee
or any of its Subsidiaries to their customers, users of the Products or any
third parties shall not bind Grantor or be deemed or treated as having been
made by Grantor, and service of any such warranty shall be the sole
responsibility of such Grantee and its Subsidiaries.

Article 7. — Confidential
Information

7.1           Each
Party has disclosed to the other Party certain proprietary technical or
business information (“Confidential Information”) during the course of the
Litigation and/or during the course of negotiating this Agreement. Each party
agrees to protect the Confidential Information of the disclosing Party,
including Confidential Information disclosed in the course of negotiating this
Agreement, from disclosure according to the terms of the Protective Order for
All

 9
 

 

Multidistrict Litigation and Related
Matters (“Protective Order”), dated November 21, 2005, and entered in the
litigation styled In Re Compression Labs, Inc. Patent
Litigation, MDL No. M:05cv01654. Each Party further agrees to return
or destroy the Confidential Information of the disclosing Party, including
Confidential Information disclosed in the course of negotiating this Agreement,
according to the terms of paragraph 27 of the Protective Order. In the event
that any third party attempts to obtain disclosure of Confidential Information
received from the disclosing Party that is not returned or destroyed, each
Party agrees to notify the disclosing Party promptly of such attempt to obtain
disclosure so that the disclosing Party may act to prevent disclosure and to
follow reasonable procedures to prevent unauthorized disclosure or use of the
Confidential Information, such reasonable procedures including, without
limitation, making all reasonable and necessary objections in response to a
subpoena or other discovery process in connection with any judicial or administrative
proceeding in order to preserve the right of either party to prevent disclosure
of its Confidential information.  Each
Party further agrees to cooperate with the other Party to prevent disclosure of
that other Party’s Confidential Information.  Each party acknowledges that it has not and in
no event shall export directly or indirectly, any technical data acquired from
the other party to any country, individual or entity for which the U.S.
Government or any agency thereof, at the time of export, requires an export
license or other governmental approval, without first obtaining the written
consent to do so from the Bureau of Industry & Security (or other agency of
the U.S. Government with applicable jurisdiction) whenever required by an applicable
statute or regulation.  “Confidential
Information” for purposes of this Section shall not include any technical,
operational, marketing or sales information produced by Grantor in any of the
Lawsuits relating to Widcom prior art devices identified in any of the
Lawsuits, including the Widcom VTC-56 and Widcom Rapics 500 devices (“Grantor’s
Widcom Documents”).  All protective order
designations (including of any “restricted” or “confidential” form) placed upon
Grantor’s Widcom Documents are hereby removed; no such information therefore
need be destroyed or returned Grantor; and each Released Party may use the
Grantor’s Widcom Documents for the defense of any other patent Infringement
litigation or proceedings, whether or not related to the ‘672 Patent, without
payment or further consent of Grantor.

7.2           Grantor
and Grantees, each on behalf of itself and its Subsidiaries, shall not disclose
the terms of this Agreement, except:

(a)   to any governmental body having
jurisdiction;

(b)   as otherwise may be required by law or
legal process (including legal requirements and regulations of the securities
and tax laws, rules and regulations);

(c)   to state that it has settled with the
other party,

(d)   to respond to any information discussed
by another party in any filings made pursuant to the regulations of the U.S.
Securities and Exchange Commission and rules of the NYSE or NASDAQ or in any
press release or other public statement;

(e)   to disclose information (excluding
Exhibit D) for bona fide business reasons, including without limitation disclosure by a Licensee
to Released Parties regarding the nature and scope of the release and license
for their benefit, disclosure by a Licensee to Permitted Agents and
Customers regarding
the scope of the release and license

 10
 

 

granted hereunder, and prospective agents or
customers and prospective Permitted Agents and Customers regarding the scope of
the license granted hereunder; and

(f)    to its attorneys, accountants, auditors,
employees or agents having a need to know.

The Parties shall have the right to
disclose the existence of this Agreement.

7.3           Notwithstanding
any provision to the contrary herein, any Party and any of its Subsidiaries is
permitted to disclose this Agreement in response to a valid subpoena or as
otherwise may be required by law, the official rules of a court or tribunal, or
court order (including discovery in a court proceeding, arbitration, regulatory
hearing, or other proceeding) under a protective order or to file or to
disclose under seal this Agreement, in whole or in part, and information
relating to this Agreement in a proceeding in any action in any court,
tribunal, or government agency of competent jurisdiction, whether brought by or
against a Party or a Subsidiary of a Party, when reasonably necessary for such
action or proceeding, subject to written notice to the other parties with a
reasonable opportunity provided to the other parties to obtain a protective
order or other restriction.

Article 8. — Limitation of
Liability

8.1           GRANTOR
SHALL NOT BE LIABLE TO ANY GRANTEE OR ANY SUBSIDIARIES OF SUCH GRANTEE, THEIR
PERMITTED AGENTS AND CUSTOMERS, THE USERS OF ANY GRANTEE’S PRODUCT OR
UNLICENSED PRODUCT, OR ANY THIRD PARTIES FOR INDIRECT, SPECIAL OR CONSEQUENTIAL
DAMAGES, INCLUDING, WITHOUT LIMITATION ANY DAMAGE OR INJURY TO BUSINESS
EARNINGS, PROFITS OR GOODWILL SUFFERED BY ANY PERSON ARISING FROM ANY USE OF
THE LICENSED PATENTS, PRODUCTS OR UNLICENSED PRODUCTS EVEN IF GRANTOR IS
ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

Article 9. — Business
Acquisition or Sale

In the event that any Grantee or any
Subsidiary of a Grantee, subsequent to the Effective Date, sells, transfers or
otherwise disposes to a third-party any subsidiary, ongoing business, or
product line covered by the licenses, covenants, or releases granted herein,
such transferred subsidiary, business, and/or product line shall continue in
all respects to be covered by the licenses, covenants, and releases herein and
otherwise entitled to the continuing protection of this Agreement.  In the event that any Grantee or any
Subsidiary of a Grantee, subsequent to the Effective Date, acquires from a
third-party any subsidiary, ongoing business, or product line, such acquired
subsidiary, business, and/or product line, to the extent that it includes any
Commercial Activities relating to Products, shall be deemed licensed under and
otherwise entitled to the protection of this Agreement.  Grantor agrees that this Agreement may not be
used adversely to any Grantee, or Subsidiary, in any action arising from any
such acquisition or divestiture.  Grantor
agrees that each Licensee shall have the right to grant sublicenses,
retroactive to the Effective Date of this Agreement, as may be necessary to
effect the provisions of this Article.

 11

 

Article 10. – Assignment of
Rights

10.1         Except
as otherwise specifically provided in this Agreement, neither this Agreement
nor any rights hereunder may be assigned or otherwise transferred by any
Grantee, in whole or in part, without the consent of either Grantor, which
shall not be unreasonably withheld, except that any Grantee may, without such
consent, assign the Agreement and its rights and obligations hereunder to any
Subsidiary or other affiliate of such Grantee, to such Grantee’s or its
Subsidiary’s successor in interest in connection with any merger, acquisition,
consolidation or sale of all or substantially all of its assets or sale of the
business unit of one or more Products to which this Agreement relates, or as
part of corporate reorganizations where the beneficial ownership of the Grantee
or its Subsidiary remains substantially the same.  Subject to the foregoing, this Agreement will
be binding upon and inure to the benefit of the Parties and their respective
successors and permitted assigns, including the covenants granted herein.
Assignees or transferees of any of the Licensed Patents shall be required to
recognize this Agreement as a condition of the transfer and such assignment or
transfer of any of the Licensed Patents shall be made subject to this
Agreement.

10.2         Except
as otherwise specifically provided in this Agreement, neither this Agreement
nor any rights hereunder may be assigned or otherwise transferred by any
Grantor, in whole or in part, without the consent of all Grantees, which shall
not be unreasonably withheld, except that any Grantor may, without such
consent, assign the Agreement and its rights and obligations hereunder to any
Subsidiary or other affiliate of such Grantor, to such Grantor’s or its
Subsidiary’s successor in interest in connection with any merger, acquisition,
consolidation or sale of all or substantially all of its assets, or as part of
corporate reorganizations where the beneficial ownership of the Grantor or its
Subsidiary remains substantially the same. 
Subject to the foregoing, this Agreement will be binding upon and inure
to the benefit of the Parties and their respective successors and permitted
assigns, including the covenants granted herein.

Article 11.

[This article has been intentionally deleted.]

Article
12. — No Joint and Several Liability

12.1         The
rights and obligations of the Grantees hereunder are several and not
joint.  Notwithstanding anything herein
to the contrary, no Grantee shall have any liability hereunder for any actions
or inactions of another Grantee (including, without limitation, any liability
for any failure by another Grantee to make a payment hereunder).  For the avoidance of doubt, if this Agreement
has become effective as set forth in Section 3.1 and if a Grantee fails to make
a payment in accordance with Section 4, such failure shall not affect the
rights or obligations of any other Grantee or Released Parties hereunder, and
all other Grantees and Released Parties shall continue to have all rights
hereunder notwithstanding such failure of any such Grantee to make such
payment.

 12
 

 

Article 13. — Miscellaneous

13.1

(a)           The
rights and obligations of the Parties under this Agreement shall be governed by
and construed in accordance with laws of the State of California, without
reference to conflicts of laws principles.

(b)           Any
dispute arising out of this Agreement shall be brought in, and each Party
irrevocably consents to the personal jurisdiction and venue of the United
States District Court for the Northern District of California or, if no subject
matter jurisdiction exists in such District, in the state courts located in
such District.  However, if any Party is
made a party to an action brought in any other jurisdiction that affects or
might reasonably be expected to affect rights under this Agreement, then such
Party may join, implead, interplead or otherwise bring another Party into such
action in such other jurisdiction so that all issues may be resolved in a
single action. This shall apply whether or not such joinder is mandatory or permissive.

(c)           Each
Party hereby irrevocably waives any objection which it may now or hereafter
have to the laying of venue of any suit, action or proceeding relating to this
Agreement in the Northern District of California (or, if no subject matter
jurisdiction exists in such District, in the state courts located in such
District) and further irrevocably waives any claim that the Northern District
of California (or, if no subject matter jurisdiction exists in such District,
in the state courts located in such District) is not a convenient forum for any
such suit, action, or proceeding.

13.2         The
terms and conditions of this Agreement may only be amended by a writing signed
by all Parties; provided, however, that as
between the Grantor and any individual Grantee, the terms and conditions of
this Agreement may be amended by a writing signed by the Grantor and such
Grantee and shall apply only to the agreement between the Grantor and such
Grantee.

13.3         Any
notice required or permitted under this Agreement or required by law must be in
writing and must be (i) delivered in person, (ii) sent by facsimile with a hard
copy of such facsimile sent by (international or domestic) registered or
(international or domestic) express or, for domestic addresses, certified mail,
postage prepaid, or (iii) sent by overnight or next business day courier such
as Federal Express, UPS or DHL, as follows:

(1)           If
to Grantor:

Forgent Networks, Inc.

Compression Labs, Inc.

108 Wild Basin Road

Austin, Texas 78746

Attention: Richard Snyder, Chairman and
CEO

Facsimile No.:
512-437-2748

Copy to:

Susman Godfrey LLP

590 Madison
Ave., 8th Floor

 13
 

 

New York, NY 10022

Attention: Tibor L. Nagy, Esq.

Telephone No. (212) 336-8330

Facsimile No. (212) 336-8340

(2)           If
to any Grantee identified in Exhibit A, to the address(es) for such
Party listed under the “Notice” column on Exhibit A, or to such other
individual or address as a Party may specify by notice hereunder.

Any Party may amend its address by
written notice to all parties in accordance with this Section.  Notice may be given by counsel to the
parties.  Notices will be deemed to have
been given at the time of actual delivery in person on a business day, five (5)
business days (7 business days for international delivery) after deposit in the
mail as set forth herein, or one (1) business day after delivery to an
overnight courier service (4 business days for international delivery).

13.4         Except
as expressly provided herein, the rights and remedies herein provided shall be
cumulative and not exclusive of any other rights or remedies provided by law or
otherwise. Subject to any applicable statute of limitations, failure by any
Party to detect, protest, or remedy any breach of this Agreement shall not
constitute a waiver or impairment of any such term or condition, or the right
of any Party at any time to avail itself of such remedies as it may have for
any breach or breaches of such term or condition. A waiver may only occur
pursuant to the express written permission of an authorized officer of the
party against whom the waiver is asserted.

13.5         In
the event any term, condition or provision of this Agreement is declared or
found by a court of competent jurisdiction to be illegal, unenforceable or
void, the Parties shall endeavor in good faith to agree to amendments that will
preserve, as far as possible, the intentions expressed in this Agreement. If
the Parties fail to agree on any such amendment, such invalid term, condition
or provision shall be severed from the remaining terms, conditions and provisions,
which shall continue to be valid and enforceable to the fullest extent
permitted by law.

13.6         This
Agreement is the result of negotiations between all Parties and accordingly
shall not be construed for or against any Party merely because such Party drafted
this Agreement or any portion thereof.

13.7         This
Agreement is, and any amendment hereof, shall be written in English.
Notwithstanding that this Agreement, or any amendment hereof, may be translated
into a different language, the English language version of this Agreement and
any such amendment shall govern.

13.8         Titles
of the Articles herein are for the convenience of reference only and shall not
affect the construction of this Agreement.

13.9         If
the Parties cannot resolve a dispute amicably after notice and a reasonable
opportunity to cure, then in the event of any legal action to enforce or
interpret the terms of this Agreement, the prevailing party shall be entitled,
in addition to its court costs, to its reasonable attorneys’ fees, including
without limitation the costs, expenses and attorneys’ fees on any appeal.

 14
 

 

13.10       Except
as specifically provided in this Agreement, nothing contained herein shall be
construed as a grant of, or as an intention or commitment to grant, to any
party other than Grantees and their Subsidiaries any right, title or interest,
of any nature whatsoever, in or to this Agreement or the license granted to
Grantees and their Subsidiaries hereunder.

13.11       This
Agreement sets forth the entire agreement and understanding between the Parties
and supersedes and cancels all previous negotiations, agreements and
commitments, whether oral or in writing, with respect to the subject matter
described herein and therein, and no Party shall be bound by any term, clause,
provision, or condition save as expressly provided in this Agreement or as duly
set forth in writing as a subsequent amendment to this Agreement, signed by
duly authorized officers of each Party, except that the Parties continue to be
bound by the terms of the Protective Order for All Multidistrict Litigation and
Related Matters, dated November 21, 2005, and entered in the litigation styled In Re Compression Labs, Inc. Patent Litigation, MDL No.
M:05cvO1654. Such Protective Order shall continue in full force and effect and shall
be deemed an agreement supplementary to this license for purposes of the United
States Bankruptcy Code. 11 USC Sect. 365(n).

13.12       This
Agreement may be executed in counterparts, each of which will be deemed an
original and all of which together constitute one instrument. Executed
counterparts of this Agreement sent and received via facsimile or electronic
transmission means shall be deemed originals for all purposes.

13.13       All
licenses granted under or pursuant to this Agreement are and shall be deemed to
be, for purpose of Section 365(n) of the U.S. Bankruptcy Code, licenses of
rights to intellectual property as defined under Section 101 of the U.S.
Bankruptcy Code, as amended. The Parties agree that the Licensee, as a licensee
of such rights under this Agreement, shall retain and may fully exercise all of
its rights and elections under the U.S. Bankruptcy Code, as amended.

13.14       United
States Patent No. 4,698,672 is in the MPEG LA’s MPEG-2 Patent
Portfolio.  Accordingly, nothing in this
Agreement shall be construed to confer a license for MPEG-2.

(REMAINDER OF PAGE INTENTIONALLY LEFT
BLANK)

 15
 

 

IN WITNESS WHEREOF, this Agreement has
been duly executed by the Parties, as dated below, to be effective as of the
Effective Date.

	
  GRANTOR

  
	
  Agreed to:

  
	
   

  
	
   

  
	
   

  
	
  By: Paul Tesluk

  
	
   

  
	
  Title: Assistant Treasurer

  
	
   

  
	
  Forgent Networks, Inc.

  
	
   

  
	
  Date: 5 October 2006

  
	
   

  

 

	
  GRANTEE

  	
   

  	
  GRANTEE

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Jim Wong

  	
   

  	
  By: Philippe
  Houssiau

  
	
   

  	
   

  	
   

  
	
  Title: Sr. Corp. VP & President of IT Products
  Business

  Group

  	
   

  	
  Title:
  President, Agfa Healthcare Business Group

  
	
   

  	
   

  	
  By: Stefaan Van
  Hooren

  
	
  ACER,
  Incorporated

  	
   

  	
   

  
	
   

  	
   

  	
  Title:
  President, Agfa Graphics Business Group

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  Agfa-Gevaert N.V.

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Lin M. Held

  	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Title: Sr. Vice President and Chief Administrative

  	
   

  	
  Title:

  	
   

  	
   

  
	
  Officer

  	
   

  	
   

  
	
   

  	
   

  	
  Canon Inc.

  
	
  BancTec, Inc.

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Scott L.
  Lampert

  	
   

  	
  By: Keh Long NG

  
	
   

  	
   

  	
   

  
	
  Title: Vice
  President and General Counsel

  	
   

  	
  Title:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Concord Camera
  Corp.

  	
   

  	
  Creative Technology, Ltd

  
						

 16
 

 

 

	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  	
   

  	
  By: Joyce Haag

  
	
   

  	
   

  	
   

  
	
  Title:

  	
   

  	
   

  	
   

  	
  Title: General
  Counsel

  
	
   

  	
   

  	
   

  
	
  Dell Inc.

  	
   

  	
  Eastman Kodak Company and Creo, Inc.

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  	
   

  	
  By: Masanobu
  Katoh

  
	
   

  	
   

  	
   

  
	
  Title:

  	
   

  	
   

  	
   

  	
  Title: Corporate Vice President Group President, Law
  &

  
	
   

  	
   

  	
  Intellectual
  Property Unit

  
	
  FUJIFILM
  Holdings Corporation

  	
   

  	
   

  
	
   

  	
   

  	
  Fujitsu Limited

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Neal West

  	
   

  	
  By: Jeffery
  Fromm

  
	
   

  	
   

  	
   

  
	
  Title: Vice
  President & Controller

  	
   

  	
  Title: Vice President, Deputy General Counsel and

  Director of Intellectual Property for HP

  
	
  Gateway, Inc.

  	
   

  	
   

  
	
   

  	
   

  	
  Hewlett Packard
  Company

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  	
   

  	
  By: Mr. Makoto
  Kawamura

  
	
   

  	
   

  	
   

  
	
  Title:

  	
   

  	
   

  	
   

  	
  Title: President

  
	
   

  	
   

  	
   

  
	
  International
  Business Machines Corporation

  	
   

  	
  Kyocera Corporation

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Title:

  	
   

  	
   

  	
   

  	
  Title:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Matsushita
  Electric Industrial Co., Ltd.

  	
   

  	
  Microsoft
  Corporation

  
									

 17
 

 

 

	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Nobuaki
  Uchida

  	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Title: General
  Manager, Corporate Licensing Division

  	
   

  	
  Title:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Mitsubishi
  Electric Corporation

  	
   

  	
  Palm, Inc.

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Yutaka Ebi

  	
   

  	
  By: Richard
  Green

  
	
   

  	
   

  	
   

  
	
  Title: Corporate Vice President Legal &
  Intellectual

  Property Division

  	
   

  	
  Title: Executive
  Vice President, Software

  
	
   

  	
   

  	
  Sun
  Microsystems, Inc.

  
	
  Ricoh Company,
  Ltd.

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  	
   

  	
  By: Matthew Zinn

  
	
   

  	
   

  	
   

  
	
  Title:

  	
   

  	
   

  	
   

  	
  Title: Senior Vice President, General Counsel,
  Secretary

  
	
   

  	
   

  	
  and Chief
  Privacy Officer

  
	
  Thomson, Inc.

  	
   

  	
   

  
	
   

  	
   

  	
  TiVo Inc.

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Taisuke Kato

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Title: General
  Manager, Intellectual Property Division

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Toshiba
  Corporation

  	
   

  	
   

  
									

 

 18

 

	
  EXHIBIT A

  	
  LIST OF GRANTEES

  

 

	
  GRANTEE

  	
   

  	
  Notice

  
	
  ACER, Incorporated

  	
   

  	
  General Counsel

  Legal Division 

  ACER, Incorporated 

  8F, 88, Sec. 1, Hsin Tai Wu Rd., 

  Hsichih Taipei Hsien 221, Taiwan, R.O.C. 

  Telephone No: 886-2-2696-1234 

  Facsimile No: 886-2-8691-1009

  
	
   

  	
   

  	
   

  
	
  Agfa-Gevaert N.V.

  	
   

  	
  Agfa-Gevaert N.V.

  Septestraat 27 

  2640 Mortsel, Belgium 

  Attn: Patrick Theunis 

  Vice President, Intellectual Property 

  Telephone No. 32 3 444 2111 

  Facsimile No. 32 3 444 7094

  
	
   

  	
   

  	
   

  
	
  BancTec, Inc.

  	
   

  	
  BancTec, Inc. 

  2701 E. Grauwyler 

  Irving, Texas 75061 

  Attention Rita Pendergrass, Corporate Counsel 

  Telephone No: 972-821-4600 

  rita.pendergrass@banctec.com

  
	
   

  	
   

  	
   

  
	
  Canon Inc.

  	
   

  	
  Senior General Manager 

  Contracts and Licensing Center 

  Corporate Intellectual Property & Legal Headquarters 

  Canon Inc. 

  30-2, Shimomaruko 3-chome 

  Ohta-ku, Tokyo 146-8501 

  Japan

  
	
   

  	
   

  	
   

  
	
  Concord Camera Corp.

  	
   

  	
  Concord Camera Corp.

  4000 Hollywood Blvd., Suite 650N 

  Hollywood, Florida 33021 

  Attention: Legal Department

  
	
   

  	
   

  	
   

  
	
  Creative Technology, Ltd

  	
   

  	
  Creative Technology, Ltd 

  31 International Business Park 

  Creative Resource 

  Singapore 609921 

  Attention: Vice President - Legal Services 

  with copy to: 

   

  Creative Labs, Inc. 

  1901 McCarthy Boulevard 

  Milpitas, California 95035 

  Attention: Director of Legal Affairs

  
	
   

  	
   

  	
   

  
	
  Dell Inc.

  	
   

  	
  Dell Inc. 

  One Dell Way 

  Round Rock, Texas 78682 

  Attention: Legal Department

  
	
   

  	
   

  	
   

  
	
  Eastman Kodak Company and Creo, Inc.

  	
   

  	
  Attention: General Counsel 

  Eastman Kodak Company 

  343 State Street 

  Rochester, NY 14650-0211

  
	
   

  	
   

  	
   

  
	
  FUJIFILM Holdings Corporation

  	
   

  	
   

  

 

 A-1
 

 

 

	
  Fujitsu Limited

  	
   

  	
  Fujitsu Limited 

  1-1, Kamikodanaka 1-chome, Nakahara-ku, 

  Kawasaki 211-8588, Japan 

  Attention: General Manager, Industry Relations Division 

  (H0460), Law & Intellectual Property Unit

  
	
   

  	
   

  	
   

  
	
  Gateway, Inc.

  	
   

  	
  General Counsel 

  Legal Department 

  Gateway, Inc. 

  7565 Irvine Center Drive 

  Irvine, California 92618 

  USA 

  With a copy to: 

   

  Director, Intellectual Property 

  Legal Department 

  Gateway, Inc. 

  7565 Irvine Center Drive 

  Irvine, California 92618

  USA

  
	
   

  	
   

  	
   

  
	
  Hewlett Packard Company

  	
   

  	
  Deputy General Counsel and Director of Intellectual
  Property 

  Hewlett-Packard Company 

  3000 Hanover Street 

  Palo Alto, California 94304-1112 

  Facsimile No. 650.852.8194

  
	
   

  	
   

  	
   

  
	
  International Business Machines Corporation

  	
   

  	
  Manager of Corporate Litigation 

  International Business Machines Corporation 

  1133 Westchester Avenue 

  White Plains, NY 10604

  
	
   

  	
   

  	
   

  
	
  Kyocera Corporation

  	
   

  	
  Kyocera Corporation, Yokohama Office, 

  Attention: Mr. Shinichirou Yamashita 

  Division Manager, Corporate Legal and Intellectual Property Division 

  2-1-1 Kagahara, Tsuzuki-ku, Yokohama-shi, Kanagawa 224-8502, Japan 

  Telephone +81-45-943-6184 

  Fax +81-45-943-6192

  
	
   

  	
   

  	
   

  
	
  Matsushita Electric Industrial Co., Ltd.

  	
   

  	
  Director, Licensing Center, 

  Intellectual Property Rights Operations Company, 

  Matsushita Electric Industrial Co., Ltd., 

  20F Matsushita IMP Building, 1-3-7, Shiromi, Chuo-ku, 

  Osaka City 540-6320, Japan 

  With a copy to: 

   

  Morton Amster, Esq. 

  Amster, Rothstein & Ebenstein, LLP 

  90 Park Avenue 

  New York, New York 10016 

  

 

 A-2
 

 

 

	
   

  	
   

  	
  Tel: 212-336-8000 

  Fax: 212-336-8001.

  
	
   

  	
   

  	
   

  
	
  Microsoft Corporation

  	
   

  	
  Attention: General Counsel 

  Microsoft Corporation 

  One Microsoft Way 

  Redmond, WA 98052 

  Facsimile: 425-936-7329 

  Copy to: 

   

  Director of Intellectual Property Licensing 

  Microsoft Corporation 

  One Microsoft Way 

  Redmond, WA 98052 

  Facsimile: 425-936-7329

  
	
   

  	
   

  	
   

  
	
  Mitsubishi Electric Corporation

  	
   

  	
  Nobuaki Uchida, General Manager 

  Corporate Licensing Division 

  Mitsubishi Electric Corporation 

  Email: uchida.nobuaki@ct.mitsubishielectric.co.jp

  
	
   

  	
   

  	
   

  
	
  Palm, Inc.

  	
   

  	
  Palm, Inc. 

  Attn: General Counsel 

  950 West Maude Avenue 

  Sunnyvale, CA 94085

  
	
   

  	
   

  	
   

  
	
  Ricoh Company, Ltd.

  	
   

  	
  Kenji Takiguchi 

  Deputy General Manager of Legal Division 

  General Manager of Legal & IP Licensing Department 

  Legal & Intellectual Property Division 

  Ricoh Company, Ltd. 

  2-3, Shin-yokohama 3-chome 

  Kohoku-ku, Yokohama 222-8350 

  Japan

  
	
   

  	
   

  	
   

  
	
  Sun Microsystems, Inc.

  	
   

  	
  Sun Microsystems, Inc. 

  10 Network Circle 

  Menlo Park, CA 94025 

  Attention: Vice President of Intellectual Property

  
	
   

  	
   

  	
   

  
	
  Thomson, Inc.

  	
   

  	
  Thomson, Inc. 

  10330 North Meridian Street 

  Indianapolis, IN 46290

  
	
   

  	
   

  	
   

  
	
  TiVo Inc.

  	
   

  	
  TiVo Inc. 

  General Counsel: Matthew Zinn 

  2160 Gold Street 

  Alviso, CA 95002 

  Fax: (408) 519-5330

  
	
   

  	
   

  	
   

  
	
  Toshiba Corporation

  	
   

  	
  1-1, Shibaura 1-Chome, Minato-ku, Tokyo 105-8001,
  Japan

  Attention: Senior Manager, Licensing & Contracts 

  Department, Intellectual Property Division 

  Telefax: +81-3-5444-9213

  

 

 A-3

 

EXHIBIT B

USPN 4,698,672 - Coding System for
Reducing Redundancy

UK and French patents — EP266049

German Patent — Registration No. 3789273

Italian Patent — Registration No. 67927/B
Ei94

(Including continuations,
divisions, or continuations-in-part and any reissues of any of these patents
and under Letters Patent which may be obtained anywhere in the World for the
inventions described therein, and to other applications or patents covering
said inventions anywhere in the World)

 B-1

 

	
  EXHIBIT C

  	
  FORM OF ORDER OF DISMISSAL WITH PREJUDICE

  

 

 C-1
 

 

DAVID C. MARCUS (158704)

STEPHEN E. MORRISSEY (187865)

SUSMAN GODFREY L.L.P.

1901 Avenue of the Stars, Suite 950

Los Angeles, CA  90067

Main Telephone:  (310) 789-3100

Main Fax:  (713) 789-3150

Email:  dmarcus@susmangodfrey.com

Email:  smorrissey@susmangodfrey.com

STEPHEN D. SUSMAN, Texas Bar 19521000 (pro hac vice)

MAX L. TRIBBLE, JR., Texas Bar 20213950 (pro hac vice)

TIBOR L. NAGY, Texas Bar 24041562 (pro hac vice)

SUSMAN GODFREY L.L.P.

1000 Louisiana, Suite 5100

Houston, TX  77002-5096

Main Telephone:  (713) 651-9366

Main Fax:  (713) 654-6666

Email: ssusman@susmangodfrey.com

Email: mtribble@susmangodfrey.com

Email:
tnagy@susmangodfrey.com

EDGAR SARGENT, Washington Bar 28283 (pro hac vice)

BROOKE TAYLOR, Washington Bar 33190 (pro hac vice)

SUSMAN GODFREY, L.L.P.

1201 Third Avenue, Suite 3100

Seattle, Washington 98101-3000

Mail Telephone:  (206) 516-3880

Main Fax:  (206) 516-3883

Email: 
esargent@susmangodfrey.com

Emial:  btaylor@susmangodfrey.com

Attorneys for Plaintiff/Declaration Judgment
Defendant

COMPRESSION LABS, INC. and

Declaratory Judgment Defendant

FORGENT NETWORKS, INC.

UNITED STATES DISTRICT COURT

NORTHERN DISTRICT OF
CALIFORNIA

SAN JOSE DIVISION

 

	
  IN
  RE COMPRESSION LABS, INC., 

  	
  Case No. M:05-CV-01654 JF 

  
	
   

  	
   

  
	
   

  	
  MDL 1657 

  
	
  PATENT LITIGATION

  	
   

  
	
   

  	
  NOTICE OF VOLUNTARY DISMISSAL OF 

  CLAIMS AS TO DELL INC. PURSUANT TO FRCP 

  41(a)(1)

  

 

 C-2
 

 

NOTICE
IS HEREBY GIVEN that pursuant to Rule 41(a) of the Federal Rules of Civil
Procedure, Plaintiff Compression Labs, Inc. in Compression
Labs v. Dell Inc. et al., C.A. No. 2-04CV-159 (E.D. Tex),
subsequently transferred to the United States District Court for the Northern
District of California and made part of the above-captioned MDL action,
voluntarily dismisses its claims against Defendant Dell Inc., in such action
and all related actions, with prejudice. 
Pursuant to the terms of a confidential settlement agreement entered
into between the parties (“Settlement Agreement”), CLI requests that this Court
retain exclusive jurisdiction over any and all disputes that may arise out of
such Settlement Agreement.  All attorneys’
fees and costs of court are to be borne by the party that incurred them.

DATED:                              ,
2006

	
  

  	
  SUSMAN GODFREY, L.L.P..

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
   

  	
  STEPHEN D. SUSMAN

  
	
   

  	
   

  	
  Texas Bar 19521000 (pro
  hac vice)

  
	
   

  	
   

  	
  MAX L. TRIBBLE, JR.

  
	
   

  	
   

  	
  Texas Bar 20213950 (pro hac vice)

  
	
   

  	
   

  	
  TIBOR L. NAGY

  
	
   

  	
   

  	
  Texas Bar 24041562 (pro hac vice)

  
	
   

  	
   

  	
  SUSMAN GODFREY L.L.P.

  
	
   

  	
   

  	
  1000 Louisiana, Suite
  5100

  
	
   

  	
   

  	
  Houston, TX 77002-5096

  
	
   

  	
   

  	
  Main Telephone: (713)
  651-9366

  
	
   

  	
   

  	
  Main Fax: (713)
  654-6666

  
	
   

  	
   

  	
  Email:
  ssusman@susmangodfrey.com

  
	
   

  	
   

  	
  Email:
  mtribble@susmangodfrey.com

  
	
   

  	
   

  	
  Email:
  tnagy@susmangodfrey.com

  
				

 

 C-3

 

David B. Weaver

VINSON & ELKINS, LLP

2801 Via Fortuna, Suite 100

Austin, TX 78746

(512) 542-8400 (phone)

(512) 236-3476 (fax)

Email:  dweaver@velaw.com

Attorneys for Defendants

Dell Inc. and BancTec,
Inc.

UNITED STATES DISTRICT COURT

NORTHERN DISTRICT OF CALIFORNIA

SAN JOSE DIVISION

	
  

  	
  Case No. M:05-CV-01654 JF 

  
	
   

  	
   

  
	
  IN RE COMPRESSION LABS, INC., 

  	
  MDL 1657 

  
	
   

  	
   

  
	
  

  PATENT LITIGATION

  	
  NOTICE OF VOLUNTARY DISMISSAL OF 

  CLAIMS AS TO COMPRESSION LABS, INC., AND

  FORGENT NETWORKS, INC. PURSUANT TO

  FED.R.CIV.P. 41 (a)(1)

  

 

 D-1
 

 

NOTICE
IS HEREBY GIVEN that pursuant to Rule 41(a) of the Federal Rules of Civil
Procedure and subject to the terms and conditions of a confidential settlement
agreement entered into between the parties (“Settlement Agreement”), Defendant
Dell Inc., in Compression Labs, Incorporated v. Dell Inc.,
C.A. No. 2-04CV-159 (E.D. Tex), subsequently transferred to the
United States District Court for the Northern District of California and made
part of the above-captioned MDL action, voluntarily dismisses its claims
against Plaintiffs Compression Labs, Inc. and Forgent Networks, Inc., in such
action and all related actions with prejudice, except for those claims,
counterclaims, and defenses related to the non-infringement, invalidity and/or
unenforceability of U.S. Patent 4,698,672, which are dismissed for want of
subject matter jurisdiction. Pursuant to the terms of the Settlement Agreement,
Dell requests that this Court retain exclusive jurisdiction over any and all disputes
that may arise out of such Settlement Agreement.  All attorneys’ fees and costs of court are to
be borne by the party that incurred them.

DATED:                                  ,
2006

	
  

  	
  VINSON & ELKINS L.L.P.

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
  David B. Weaver

  
	
   

  	
  2801 Via Fortuna, Suite
  100

  
	
   

  	
  Austin, Texas
  78746-7568

  
	
   

  	
  Telephone: 512.542.8651

  
	
   

  	
  Fax: 512.236.3476

  
	
   

  	
  Email:
  dweaver@velaw.com

  
				

 

 D-2

 

EXHIBIT E

RELEASE AND AGREEMENT TO DISMISS

This Release
and Agreement to Dismiss (the “Release”) is being delivered effective                             ,
2006 (the “Effective Date”) by General Instrument Corp., on behalf of itself
and its affiliates and subsidiaries (“General Instrument”), concurrently with
the delivery of that certain Patent License and Settlement Agreement (“Agreement”),
entered into by and between FORGENT NETWORKS, INC. and its wholly-owned
subsidiary, COMPRESSION LABS, INC., and the parties listed on Schedule 1 hereto
(each referred to separately as a “Party” or collectively as the “Parties”), in
light of the following facts:

A.            The
following lawsuits have been commenced by some of the Parties against General
Instrument (the “Lawsuits”):

Agfa Corp. et al. v. Compression Labs, Inc., et
al., C.A. No. 04-818 (D. Del.);

Yahoo! Inc. v. Compression Labs, Inc., et al.,
C.A. No. 07-918 (D. Del.);

Audiovox Corp. et al. Compression Labs, Inc., et
al., No. 04-1293 (D. Del.);

which cases have been consolidated in the United
States District Court for the Northern District of California (“ND Calif.”) for
pretrial purposes, as set forth in the Multidistrict Litigation Panel Order
dated February 16, 2005 (“In Re Compression Labs, Inc. Patent Litigation, MDL
No. M:05cv01654”).

B.            General
Instrument at one time had an interest in the Patent.

C.            General
Instrument and the Parties now desire to avoid further litigation risks and
expense, and seek a settlement of the Lawsuits in exchange for releases, all on
the terms and conditions set forth herein.

NOW, THEREFORE,
in consideration of the above premises and the mutual covenants and obligations
herein and other good and valuable consideration, General Instruments and the
Parties hereby agree as follows:

1.             Scope
of General Release.  In consideration of
the agreement to dismiss contained herein and other good and valuable
consideration, and on behalf of its affiliates, subsidiaries successors, and
assigns, General Instruments hereby fully and forever releases and discharges
each Party and the affiliates, subsidiaries successors, and assigns of each
Party, and each of its and their Permitted Agents and Customers (individually,
each a “Released Party” and collectively, the “Released Parties”) of any and
all causes of action, actions, rights of action, suits, judgments, liens,
indebtedness, damages, losses, claims, liabilities, obligations, attorneys’
fees, costs, expenses, and demands of every kind and character (each, a “Claim”),
whether known or unknown, suspected or unsuspected, disclosed or undisclosed,
each of which is a Claim (i) for patent infringement of the Patent or (ii)
arising out of or resulting from or in any way related to the Lawsuits.

2.             Definitions.  As used in this Release, capitalized terms
not otherwise defined have the same meaning as in the Agreement.

3.             Quit
Claim.  To the extent General Instrument
may have any current or ongoing ownership or rights in the Patent, General
Instrument agrees that it will not, at any time or in any capacity, assert any
claim or commence or prosecute any action, suit or proceeding, or assist any
third party or affiliated party to assert any claim or commence or prosecute
any action, suit or proceeding, against any Released Parties for infringement
of the Patent.

 E-1
 

 

4.             Waiver.  All rights under Section 1542 of the Civil
Code of the State of California, and under any and all similar laws of any
governmental entity, are hereby expressly waived.  Each party is aware that said Section 1542 of
the Civil Code provides as follows:

“A GENERAL RELEASE DOES NOT EXTEND TO
CLAIMS WHICH THE CREDITOR DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT THE
TIME OF EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY
AFFECTED HIS SETTLEMENT WITH THE DEBTOR.”

5.             Full
Settlement.  The Parties and General
Instrument agree that this Agreement is in full and complete settlement of the
rights and obligations of the parties in connection with the Patent and the
Lawsuits.  This Agreement may be pleaded
as full and complete defense to any action, suit or claim and may be used as an
injunction against any such action, suit, claim, or other proceeding of any
type which may be prosecuted, initiated or attempted in violation of the terms
hereof.

6.             Dismissal.  Each Party with a suit against General
Instrument shall, within five (5) business days of receipt of this Release,
fully executed by General Instrument and each other Party, file a signed copy
of a notice of voluntary dismissal of claims as to General Instrument pursuant
to FRCP 41(a)(1).

7.             Not
an Admission.  It is understood that this
Release does not constitute an admission of any liability by any party, but is
a compromise of disputed claims.  Neither
this Release, the dismissal of any of the Lawsuits, nor any action undertaken
pursuant thereto or hereto, constitutes or shall be construed as an admission
by any Released Party with respect to any claim or defense including but not
limited to contentions of Infringement or validity or enforceability of any
Licensed Patent.

IN WITNESS WHEREOF,
this Agreement has been duly executed by the Parties, as dated below, to be
effective as of the Effective Date.

	
  General Instruments
  Corporation

  
	
  Agreed to:

  
	
   

  
	
   

  
	
  By:

  	
   

  	
   

  
	
   

  
	
  Title:

  	
   

  	
   

  
	
   

  
	
  General
  Instruments Corporation

  
	
   

  
	
  Date:

  	
   

  	
  , 2006

  
							

 

	
  GRANTEE

  	
   

  	
  GRANTEE

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Jim Wong

  	
   

  	
  By: Philippe Houssiau

  
	
   

  	
   

  	
   

  
	
  Title: Sr. Corp.
  VP & President of IT Products Business

  	
   

  	
  Title: President, Agfa Healthcare Business Group

  
	
   

  	
  Group

  	
   

  	
   

  
				

 

 E-2
 

 

 

	
  ACER, Incorporated

  	
   

  	
  By: Stefaan Van Hooren

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  Title: President, Agfa Graphics Business Group

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  Agfa-Gevaert N.V.

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Lin M. Held

  	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Title: Sr. Vice
  President and Chief Administrative 

  	
   

  	
  Title:

  	
   

  	
   

  
	
   

  	
  Officer

  	
   

  	
   

  
	
   

  	
   

  	
  Canon Inc.

  
	
  BancTec, Inc.

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Scott L.
  Lampert

  	
   

  	
  By: Keh Long NG

  
	
   

  	
   

  	
   

  
	
  Title: Vice
  President and General Counsel

  	
   

  	
  Title:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Concord Camera
  Corp.

  	
   

  	
  Creative Technology, Ltd

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  	
   

  	
  By: Joyce Haag

  
	
   

  	
   

  	
   

  
	
  Title:

  	
   

  	
   

  	
   

  	
  Title: General Counsel

  
	
   

  	
   

  	
   

  
	
  Dell Inc.

  	
   

  	
  Eastman Kodak Company and Creo, Inc.

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  	
   

  	
  By: Masanobu Katoh

  
	
   

  	
   

  	
   

  
	
  Title:

  	
   

  	
   

  	
   

  	
  Title: Corporate Vice President Group President, Law
  &

  
	
   

  	
   

  	
  Intellectual
  Property Unit

  
	
  FUJIFILM
  Holdings Corporation

  	
   

  	
   

  
	
   

  	
   

  	
  Fujitsu Limited

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
														

 

 E-3
 

 

 

	
  By: Neal West

  	
   

  	
  By: Jeffery Fromm

  
	
   

  	
   

  	
   

  
	
  Title: Vice
  President & Controller

  	
   

  	
  Title: Vice President, Deputy General Counsel and

  
	
   

  	
   

  	
   

  	
  Director of Intellectual Property for HP

  
	
  Gateway, Inc.

  	
   

  	
   

  
	
   

  	
   

  	
  Hewlett Packard Company

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  	
   

  	
  By: Mr. Makoto Kawamura

  
	
   

  	
   

  	
   

  
	
  Title:

  	
   

  	
   

  	
   

  	
  Title: President

  
	
   

  	
   

  	
   

  
	
  International
  Business Machines Corporation

  	
   

  	
  Kyocera Corporation

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Title:

  	
   

  	
   

  	
   

  	
  Title:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Matsushita
  Electric Industrial Co., Ltd.

  	
   

  	
  Microsoft Corporation

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Nobuaki
  Uchida

  	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Title: General
  Manager, Corporate Licensing Division

  	
   

  	
  Title:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Mitsubishi
  Electric Corporation

  	
   

  	
  Palm, Inc.

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Yutaka Ebi

  	
   

  	
  By: Richard Green

  
	
   

  	
   

  	
   

  
	
  Title: Corporate
  Vice President Legal & Intellectual

  	
   

  	
  Title: Executive Vice President, Software

  
	
  Property Division

  	
   

  	
   

  
	
   

  	
   

  	
  Sun Microsystems, Inc.

  
	
  Ricoh Company,
  Ltd.

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
  Agreed to:

  
	
   

  	
   

  	
   

  
														

 

 E-4
 

 

 

	
  By:

  	
   

  	
   

  	
   

  	
  By: Matthew Zinn

  
	
   

  	
   

  	
   

  
	
  Title:

  	
   

  	
   

  	
   

  	
  Title: Senior Vice President, General Counsel,
  Secretary

  
	
   

  	
   

  	
   

  	
  and Chief Privacy Officer

  
	
  Thomson, Inc.

  	
   

  	
   

  
	
   

  	
   

  	
  TiVo Inc.

  
	
   

  	
   

  	
   

  
	
  Agreed to:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By: Taisuke Kato

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Title: General
  Manager, Intellectual Property Division

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  Toshiba
  Corporation

  	
   

  	
   

  
							

 

 E-5

 

EXHIBIT F

ARTICLE 4.3 GRANTEES

GRANTEE:

ACER, Incorporated

Canon Inc.

Creative Technology, Ltd

FUJIFILM Holdings Corporation

Fujitsu Limited

Kyocera Corporation

Matsushita Electric Corp. of America

JVC Americas Corporation

Panasonic Corporation of North America

Mitsubishi Electric Corporation

Ricoh Corporation

Toshiba CorporationEXHIBIT 4.1
  EXECUTION COPY
 

UNITED THERAPEUTICS CORPORATION

0.50% CONVERTIBLE SENIOR NOTES DUE OCTOBER 15, 2011

INDENTURE

DATED AS OF OCTOBER 30, 2006

THE BANK OF NEW YORK,

AS TRUSTEE

   
 

TABLE OF CONTENTS

	
  

  	
  

  	
  Page

  
	
   

  	
  ARTICLE
  1

  	
   

  
	
   

  	
  DEFINITIONS
  AND INCORPORATION BY REFERENCE

  	
   

  
	
  Section 1.01.

  	
  Definitions

  	
  1

  
	
  Section 1.02.

  	
  Other Definitions

  	
  7

  
	
  Section 1.03.

  	
  Trust Indenture Act Provisions

  	
  8

  
	
  Section 1.04.

  	
  Rules of Construction

  	
  8

  
	
   

  	
   

  	
   

  
	
   

  	
  ARTICLE
  2

  	
   

  
	
   

  	
  THE
  SECURITIES

  	
   

  
	
  Section 2.01.

  	
  Form and Dating

  	
  9

  
	
  Section 2.02.

  	
  Execution and Authentication

  	
  10

  
	
  Section 2.03.

  	
  Registrar, Paying Agent and Conversion Agent

  	
  11

  
	
  Section 2.04.

  	
  Paying Agent to Hold Money in Trust

  	
  12

  
	
  Section 2.05.

  	
  Securityholder Lists

  	
  12

  
	
  Section 2.06.

  	
  Transfer and Exchange

  	
  12

  
	
  Section 2.07.

  	
  Replacement Securities

  	
  14

  
	
  Section 2.08.

  	
  Outstanding Securities

  	
  15

  
	
  Section 2.09.

  	
  Treasury Securities

  	
  15

  
	
  Section 2.10.

  	
  Temporary Securities

  	
  16

  
	
  Section 2.11.

  	
  Cancellation

  	
  16

  
	
  Section 2.12.

  	
  Legends; Additional Transfer Requirements

  	
  16

  
	
  Section 2.13.

  	
  Cusip or ISIN Numbers

  	
  21

  
	
  Section 2.14.

  	
  Form of Certificate To Be Delivered in Connection
  with Transfers to 

  Institutional Accredited Investors

  	
  21

  
	
  Section 2.15.

  	
  Issuance, Transfer and Exchange of Common Stock
  Issuable Upon 

  Conversion of the Securities

  	
  23

  
	
  Section 2.16.

  	
  Additional Securities

  	
  24

  
	
  Section 2.17.

  	
  Liquidated Damages

  	
  25

  
	
   

  	
   

  	
   

  
	
   

  	
  ARTICLE
  3

  	
   

  
	
   

  	
  PURCHASES
  OF SECURITIES UPON FUNDAMENTAL CHANGE

  	
   

  
	
   

  	
   

  	
   

  
	
  Section 3.01.

  	
  Purchase of Securities at Option of the Holder Upon
  Fundamental Change

  	
  25

  
	
  Section 3.02.

  	
  Effect of Fundamental Change Purchase Notice

  	
  28

  
	
  Section 3.03.

  	
  Deposit of Fundamental Change Purchase Price

  	
  29

  
	
  Section 3.04.

  	
  Securities Purchased in Part

  	
  29

  
	
  Section 3.05.

  	
  Compliance with Securities Laws Upon Purchase of
  Securities

  	
  29

  
	
  Section 3.06.

  	
  No Purchase Upon Acceleration

  	
  30

  
	
  Section 3.07.

  	
  Trustee’s Fundamental Change Purchase Disclaimer

  	
  30

  

 

 i
 

 

	
  

  	
   

  	
  Page

  
	
   

  	
  ARTICLE
  4

  	
   

  
	
   

  	
  PAYMENT
  OF INTEREST AND ADDITIONAL SHARES

  	
   

  
	
  Section 4.01.

  	
  Interest Payments

  	
  30

  
	
  Section 4.02.

  	
  Additional Shares

  	
  31

  
	
   

  	
   

  	
   

  
	
   

  	
  ARTICLE
  5

  	
   

  
	
   

  	
  CONVERSION

  	
   

  
	
  Section 5.01.

  	
  Conversion Privilege

  	
  32

  
	
  Section 5.02.

  	
  Conversion Procedure

  	
  35

  
	
  Section 5.03.

  	
  Fractional Shares

  	
  36

  
	
  Section 5.04.

  	
  Taxes on Conversion

  	
  36

  
	
  Section 5.05.

  	
  Payment Upon Conversion

  	
  36

  
	
  Section 5.06.

  	
  Adjustment of Conversion Price

  	
  38

  
	
  Section 5.07.

  	
  No Adjustment

  	
  43

  
	
  Section 5.08.

  	
  Adjustment for Tax Purposes

  	
  44

  
	
  Section 5.09.

  	
  Temporary Reduction of Conversion Price

  	
  44

  
	
  Section 5.10.

  	
  Notice of Certain Transactions

  	
  44

  
	
  Section 5.11.

  	
  Effect of Reclassification, Consolidation, Merger or
  Sale on Conversion Privilege

  	
  45

  
	
  Section 5.12.

  	
  Disclaimer

  	
  46

  
	
  Section 5.13.

  	
  Limitation on Adjustments

  	
  46

  
	
   

  	
   

  	
   

  
	
   

  	
  ARTICLE
  6

  	
   

  
	
   

  	
  [RESERVED]

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
  ARTICLE
  7

  	
   

  
	
   

  	
  COVENANTS

  	
   

  
	
  Section 7.01.

  	
  Payment of Securities

  	
  47

  
	
  Section 7.02.

  	
  SEC Reports

  	
  47

  
	
  Section 7.03.

  	
  Maintenance of Listing

  	
  48

  
	
  Section 7.04.

  	
  Compliance Certificates

  	
  48

  
	
  Section 7.05.

  	
  Liquidated Damages Notice

  	
  48

  
	
  Section 7.06.

  	
  Rule 144A Information Requirements

  	
  48

  
	
  Section 7.07.

  	
  Further Instruments and Acts

  	
  49

  
	
  Section 7.08.

  	
  Maintenance of Corporate Existence

  	
  49

  
	
  Section 7.09.

  	
  Stay, Extension and Usury Laws

  	
  49

  

 

	
  

  	
  ARTICLE
  8

  	
   

  
	
   

  	
  CONSOLIDATION,
  MERGER, CONVEYANCE, TRANSFER OR LEASE

  	
   

  
	
  Section 8.01.

  	
  Company May Consolidate, etc., only on Certain
  Terms

  	
  49

  
	
  Section 8.02.

  	
  Successor Substituted

  	
  50

  

 

 ii
 

 

	
  

  	
   

  	
  Page

  
	
   

  	
  ARTICLE
  9

  	
   

  
	
   

  	
  DEFAULT
  AND REMEDIES

  	
   

  
	
  Section 9.01.

  	
  Events of Default

  	
  50

  
	
  Section 9.02.

  	
  Acceleration

  	
  52

  
	
  Section 9.03.

  	
  Other Remedies

  	
  53

  
	
  Section 9.04.

  	
  Waiver of Defaults and Events of Default

  	
  53

  
	
  Section 9.05.

  	
  Control by Majority

  	
  53

  
	
  Section 9.06.

  	
  Limitations on Suits

  	
  53

  
	
  Section 9.07.

  	
  Rights of Holders to Receive Payment and to Convert

  	
  54

  
	
  Section 9.08.

  	
  Collection Suit by Trustee

  	
  54

  
	
  Section 9.09.

  	
  Trustee May File Proofs of Claim

  	
  54

  
	
  Section 9.10.

  	
  Priorities

  	
  55

  
	
  Section 9.11.

  	
  Undertaking for Costs

  	
  55

  
	
   

  	
   

  	
   

  
	
   

  	
  ARTICLE
  10

  	
   

  
	
   

  	
  TRUSTEE

  	
   

  
	
  Section 10.01.

  	
  Duties of Trustee

  	
  55

  
	
  Section 10.02.

  	
  Rights of Trustee

  	
  57

  
	
  Section 10.03.

  	
  Individual Rights of Trustee

  	
  58

  
	
  Section 10.04.

  	
  Trustee’s Disclaimer

  	
  58

  
	
  Section 10.05.

  	
  Notice of Default or Events of Default

  	
  58

  
	
  Section 10.06.

  	
  Reports by Trustee to Holders

  	
  59

  
	
  Section 10.07.

  	
  Compensation and Indemnity

  	
  59

  
	
  Section 10.08.

  	
  Replacement of Trustee

  	
  60

  
	
  Section 10.09.

  	
  Successor Trustee by Merger, etc

  	
  61

  
	
  Section 10.10.

  	
  Eligibility; Disqualification

  	
  61

  
	
  Section 10.11.

  	
  Preferential Collection of Claims Against Company

  	
  61

  
	
  Section 10.12.

  	
  Trustee or Agents May Hold Securities

  	
  61

  
	
   

  	
   

  	
   

  
	
   

  	
  ARTICLE
  11

  	
   

  
	
   

  	
  SATISFACTION
  AND DISCHARGE

  	
   

  
	
  Section 11.01.

  	
  Satisfaction and Discharge

  	
  61

  
	
  Section 11.02.

  	
  Application of Trust Money

  	
  62

  
	
  Section 11.03.

  	
  Repayment to Company

  	
  62

  
	
  Section 11.04.

  	
  Reinstatement

  	
  63

  
	
   

  	
   

  	
   

  
	
   

  	
  ARTICLE
  12

  	
   

  
	
   

  	
  AMENDMENTS,
  SUPPLEMENTS AND WAIVERS

  	
   

  
	
  Section 12.01.

  	
  Without Consent of Holders

  	
  63

  
	
  Section 12.02.

  	
  With Consent of Holders

  	
  64

  
	
  Section 12.03.

  	
  Compliance with Trust Indenture Act

  	
  65

  
	
  Section 12.04.

  	
  Revocation and Effect of Consents

  	
  65

  

 

 iii
 

 

	
  

  	
   

  	
  Page

  
	
  Section 12.05.

  	
  Notation on or Exchange of Securities

  	
  65

  
	
  Section 12.06.

  	
  Trustee to Sign Amendments, etc

  	
  65

  
	
  Section 12.07.

  	
  Effect of Supplemental Indentures

  	
  66

  
	
   

  	
   

  	
   

  
	
   

  	
  ARTICLE
  13

  	
   

  
	
   

  	
  MISCELLANEOUS

  	
   

  
	
  Section 13.01.

  	
  Trust Indenture Act Controls

  	
  66

  
	
  Section 13.02.

  	
  Notices

  	
  66

  
	
  Section 13.03.

  	
  Communications by Holders with Other Holders

  	
  67

  
	
  Section 13.04.

  	
  Certificate and Opinion as to Conditions Precedent

  	
  67

  
	
  Section 13.05.

  	
  Record Date for Vote or Consent of Securityholders

  	
  68

  
	
  Section 13.06.

  	
  Rules by Trustee, Paying Agent, Registrar and
  Conversion Agent

  	
  68

  
	
  Section 13.07.

  	
  Legal Holidays

  	
  68

  
	
  Section 13.08.

  	
  Governing Law

  	
  68

  
	
  Section 13.09.

  	
  No Adverse Interpretation of Other Agreements

  	
  68

  
	
  Section 13.10.

  	
  No Recourse against Others

  	
  68

  
	
  Section 13.11.

  	
  Successors

  	
  69

  
	
  Section 13.12.

  	
  Multiple Counterparts

  	
  69

  
	
  Section 13.13.

  	
  Severability

  	
  69

  
	
  Section 13.14.

  	
  Table of Contents, Headings, etc

  	
  69

  
	
  Section 13.15.

  	
  Qualification of Indenture

  	
  69

  
	
  Section 13.16.

  	
  Force Majeure

  	
  69

  
	
   

  	
   

  	
   

  
	
  Schedule 4.02.

  	
  Additional Shares Table

  	
  S-1

  
	
   

  	
   

  	
   

  
	
  Exhibit A

  	
  Form of Security

  	
  A-1

  
	
  Exhibit B

  	
  Form of Transfer Certificate for Transfer of
  Restricted Common Stock

  	
  B-1

  

 iv
 

CROSS-REFERENCE
TABLE

	
  TIA

  SECTION

  	
   

  	
  INDENTURE

  SECTION

  
	
  Section

  	
  310(a)(1)

  	
  10.10

  
	
   

  	
  (a)(2)

  	
  10.10

  
	
   

  	
  (a)(3)

  	
  N.A.**

  
	
   

  	
  (a)(4)

  	
  N.A.

  
	
   

  	
  (a)(5)

  	
  10.10

  
	
   

  	
  (b)

  	
  10.08; 10.10

  
	
   

  	
  (c)

  	
  N.A.

  
	
  Section

  	
  311(a)

  	
  10.11

  
	
   

  	
  (b)

  	
  10.11

  
	
   

  	
  (c)

  	
  N.A.

  
	
  Section

  	
  312(a)

  	
  2.05

  
	
   

  	
  (b)

  	
  13.03

  
	
   

  	
  (c)

  	
  13.03

  
	
  Section

  	
  313(a)

  	
  10.06

  
	
   

  	
  (b)(1)

  	
  N.A.

  
	
   

  	
  (b)(2)

  	
  10.06

  
	
   

  	
  (c)

  	
  10.06; 13.02

  
	
   

  	
  (d)

  	
  10.06

  
	
  Section

  	
  314(a)

  	
  7.02; 7.07; 13.02

  
	
   

  	
  (b)

  	
  N.A.

  
	
   

  	
  (c)(1)

  	
  13.04(a)

  
	
   

  	
  (c)(2)

  	
  13.04(a)

  
	
   

  	
  (c)(3)

  	
  N.A.

  
	
   

  	
  (d)

  	
  N.A.

  
	
   

  	
  (e)

  	
  13.04(b)

  
	
   

  	
  (f)

  	
  N.A.

  
	
  Section

  	
  315(a)

  	
  10.01(b)

  
	
   

  	
  (b)

  	
  10.05; 13.02

  
	
   

  	
  (c)

  	
  10.01(a)

  
	
   

  	
  (d)

  	
  10.01(c)

  
	
   

  	
  (e)

  	
  9.11

  
	
  Section

  	
  316(a)(last sentence)

  	
  2.09

  
	
   

  	
  (a)(1)(A)

  	
  9.05

  
	
   

  	
  (a)(1)(B)

  	
  9.04

  
	
   

  	
  (a)(2)

  	
  N.A.

  
	
   

  	
  (b)

  	
  9.07

  
	
   

  	
  (c)

  	
  13.05

  
	
  Section

  	
  317(a)(1)

  	
  9.08

  
	
   

  	
  (a)(2)

  	
  9.09

  
	
   

  	
  (b)

  	
  2.04

  

*                    This Cross-Reference Table shall not, for any
purpose, be deemed a part of this Indenture.

**             N.A.
means Not Applicable.

 v

 

THIS INDENTURE, dated as of October 30, 2006, is
between United Therapeutics Corporation, a corporation duly organized under the
laws of Delaware (the “Company”), and The Bank of
New York, a New York banking corporation having its principal office at
101 Barclay Street, New York, New York 10286, as Trustee (the “Trustee”).

In consideration of the premises and the acquisition
of the Securities by the Holders thereof, both parties agree as follows for the
benefit of the other and for the equal and ratable benefit of the registered
Holders of the Securities.

ARTICLE 1     DEFINITIONS AND INCORPORATION BY REFERENCE

Section 1.01.   Definitions.

“Affiliate”
means, with respect to any specified person, any other person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified person.  For
the purposes of this definition, “control” when used with respect to any person
means the power to direct the management and policies of such person, directly
or indirectly, whether through the ownership of voting securities, by contract
or otherwise; and the terms “controlling” and “controlled” have meanings
correlative to the foregoing.

“Agent” means
any Registrar, Paying Agent or Conversion Agent.

“Applicable Procedures”
means, with respect to any transfer or exchange of beneficial ownership
interests in a Global Security, the rules and procedures of the
Depositary, in each case to the extent applicable to such transfer or exchange.

“Board of Directors”
means either the board of directors of the Company or any committee of the
Board of Directors specifically authorized to act for it with respect to this
Indenture.

“Business Day”
means each day that is not a Legal Holiday.

“Capital Stock”
of any Person means any and all shares, interests, rights to purchase,
warrants, options, participations or other equivalents of or interests in
(however designated) equity of such Person, but excluding any debt securities
convertible into such equity.

“Cash” or “cash”
means such coin or currency of the United States as at any time of payment is
legal tender for the payment of public and private debts.

“Certificated Security”
means a Security that is in substantially the form attached hereto as Exhibit A
and that does not include the information or the schedule called for by
footnotes 1, 3 and 4 thereof.

“Closing Sale Price”
of the Common Stock means, as of any date of determination, the closing per
share sale price (or, if no such closing sale price is reported on such day,
the average of the bid and asked prices or, if more than one in either case,
the average of the average bid and the average asked prices) at 4:00 p.m.,
New York City time, on such date as reported in composite transactions for the
principal U.S. national or regional securities exchange on which 

 1
 

 

the Common Stock is
traded or, if the Common Stock is not listed on a U.S. national or regional
securities exchange, as reported by the National Quotation Bureau Incorporated.

“Common Stock”
means the common stock of the Company, $0.01 par value, as it exists on the
date of this Indenture and any shares of any class or classes of Capital Stock
of the Company resulting from any reclassification or reclassifications thereof
and which have no preference in respect of dividends or of amounts payable in
the event of any voluntary or involuntary liquidation, dissolution or
winding-up of the Company and which are not subject to redemption by the
Company; provided, however, that, if at any time
there shall be more than one such resulting class, the shares of each such
class then so issuable on conversion of the Securities shall be substantially
in the proportion which the total number of shares of such class resulting from
all such reclassifications bears to the total number of shares of all such classes
resulting from all such reclassifications.

“Company” means
the party named as such in the first paragraph of this Indenture until a
successor replaces it pursuant to the applicable provisions of this Indenture,
and thereafter “Company” shall
mean such successor.

“Continuing
Directors” means, as of any date of determination, any member of the
Board of Directors who (a) was a member of the Board of Directors as of the
date hereof or (b) was nominated for election or elected to the Board of
Directors with the approval of a majority of the Continuing Directors who were
members of the Board of Directors at the time of such nomination or election.

“Conversion Rate”
means, as of any date of determination, an amount equal to $1,000 divided by
the then applicable Conversion Price on such date.  As of the date hereof and subject to
adjustment pursuant to Section 5.06, the Conversion Rate with respect to
the Securities is approximately 13.2933 shares of Common
Stock, rounded to the nearest 1/10,000th of a share, for each $1,000 principal
amount of the Securities.

“Conversion Value”
of a Security means, as of any date of determination, the product of the
Closing Sale Price of the Common Stock on such date multiplied by the then
current Conversion Rate of such Security on such date.

“Corporate Trust Office”
means the office of the Trustee at which at any time the trust created by this
Indenture shall be administered, which office at the date of the execution of
this Indenture is located at 101 Barclay Street, New York, New York 10286,
Attention: Corporate Trust Administration, or at any other time at such
other address as the Trustee may designate from time to time by notice to the
Company or the principal corporate trust office of any successor Trustee (or such
other address as such successor Trustee may designate from time to time by
notice to the Company).

“Default” or “default” means any event which is or, after notice or
passage of time or both, would be an Event of Default.

“Exchange Act”
means the Securities Exchange Act of 1934, as amended, and the rules and
regulations promulgated thereunder, as in effect from time to time.

 2
 

 

“Final Maturity Date”
means October 15, 2011.

“GAAP” means
generally accepted accounting principles in the United States of America as in
effect as of the date of this Indenture, including those set forth in
(1) the opinions and pronouncements of the Accounting Principles Board of
the American Institute of Certified Public Accountants, (2) the statements
and pronouncements of the Financial Accounting Standards Board, (3) such
other statements by such other entity as approved by a significant segment of
the accounting profession and (4) the rules and regulations of the
SEC governing the inclusion of financial statements (including pro forma financial
statements) in registration statements filed under the Securities Act and
periodic reports required to be filed pursuant to Section 13 of the
Exchange Act, including opinions and pronouncements in staff accounting
bulletins and other official written statements from the accounting staff of
the SEC expressing the views of the SEC therein.

“Global Security”
means a permanent Global Security that is in substantially the form attached
hereto as Exhibit A and that includes the information and
schedule called for by footnotes 1, 3 and 4 thereof and which is deposited
with the Depositary or its custodian and registered in the name of the
Depositary or its nominee.

“Holder” or “Securityholder” means the person in whose name a Security is
registered on the Primary Registrar’s books.

“IAI”
means institutional accredited investors (as defined in Rules 501(a)(1), (2),
(3) and (7) under the Securities Act) who are not QIBs.

“Indebtedness”
means, with respect to any Person, without duplication, (a) all
indebtedness, obligations and other liabilities (contingent or otherwise) of
such Person (i) for borrowed money (including obligations of such Person
in respect of overdrafts, foreign exchange contracts, currency exchange
agreements, interest rate protection agreements and any loans or advances from
banks, whether or not evidenced by notes or similar instruments) or
(ii) evidenced by credit or loan agreements, bonds, debentures, notes or
similar instruments (whether or not the recourse of the lender is to the whole
of the assets of such Person or to only a portion thereof) (other than any
accounts payable or other accrued current liability or obligation incurred in
the ordinary course of business in connection with the obtaining of materials
or services), (b) all reimbursement obligations and other liabilities
(contingent or otherwise) of such Person with respect to letters of credit,
bank guarantees or bankers’ acceptances, (c) all obligations and
liabilities (contingent or otherwise) of such Person (i) in respect of leases
of such Person required, in conformity with GAAP, to be accounted for as
capitalized lease obligations on the balance sheet of such Person, or
(ii) under any lease or related document (including a purchase agreement,
conditional sale or other title retention agreement) in connection with the
lease of real property or improvements thereon (or any personal property
included as part of any such lease) which provides that such Person is
contractually obligated to purchase or cause a third party to purchase the
leased property or pay an agreed upon residual value of the leased property to
the lessor (whether or not such lease transaction is characterized as an
operating lease or a capitalized lease in accordance with GAAP), (d) all
obligations (contingent or otherwise) of such Person with respect to any
interest rate or other swap, cap, floor or collar agreement, hedge agreement,
forward contract or other similar instrument or agreement or foreign currency
hedge, 

 3
 

 

exchange, purchase or
similar instrument or agreement; (e) all direct or indirect guaranties,
agreements to be jointly liable or similar agreements by such Person in respect
of, and obligations or liabilities of such Person to purchase or otherwise
acquire or otherwise assure a creditor against loss in respect of,
indebtedness, obligations or liabilities of another Person of the kind
described in clauses (a) through (d), and (f) any and all deferrals,
renewals, extensions, refinancings and refundings of, or amendments,
modifications or supplements to, any indebtedness, obligation or liability of
the kind described in clauses (a) through (e).

“Indenture”
means this Indenture as amended or supplemented from time to time pursuant to
the terms of this Indenture.

“Initial Issue Date” means
October 30, 2006.

“Initial Purchaser”
shall mean Deutsche Bank Securities Inc.

“Instrument”
means any bond, debenture, note or other evidence of Indebtedness for money
borrowed by the Company or any Significant Subsidiary (all or substantially all
of the outstanding voting securities of which are owned, directly or
indirectly, by the Company) or 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 the Company or any Significant Subsidiary
(all or substantially all of the outstanding voting securities of which are
owned, directly or indirectly, by the Company).

“interest”, in
respect of the Securities, unless the context otherwise requires, refers to
interest payable on the Securities, including Liquidated Damages, if any.

“Liquidated Damages” means
(a) “Liquidated Damages” as specified in any Registration Rights Agreement,
including the Registration Rights Agreement dated October 30, 2006 between
the Company and the Initial Purchaser and (b) any liquidated damages payable
pursuant to Section 9.01 hereof.

“Market Disruption
Event” means the occurrence or existence for more than one half hour
period in the aggregate on any scheduled Trading Day for the Common Stock of
any suspension or limitation imposed on trading, by reason of movements in
price exceeding limits permitted by NASDAQ or otherwise, in the Common Stock or
in any options, contracts or future contracts relating to the Common Stock, and
such suspension or limitation occurs or exists at any time before 1:00 p.m.
(New York City time) on such day.

“NASDAQ” means
The NASDAQ Global Select Market.

“Officer” means
the Chairman or any Co-Chairman of the Board of Directors, any Vice Chairman of
the Board of Directors, the Chief Executive Officer, the President, any Vice
President, the Chief Financial Officer, the Controller, the Secretary or any
Assistant Controller or Assistant Secretary of the Company.

“Officers’ Certificate”
means a certificate signed on behalf of the Company by two or more Officers of
the Company, one of whom must be either the principal executive officer, the 

 4
 

 

principal financial
officer or the principal accounting officer of the Company, delivered to the
Trustee, that meets the requirements of Section 13.04.

“Opinion of Counsel”
means a written opinion that meets the requirements of Section 13.04 from legal
counsel that is reasonably acceptable to the Trustee.  The counsel may be an employee of or counsel
to the Company.

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

“Principal” or “principal” of a debt security, including the Securities,
means the principal of the security plus, when appropriate, the premium, if
any, on the security.

“QIB”
means any “qualified institutional buyer” (as defined in Rule 144A).

“Qualifying Change
in Control” means any Change in Control included in clause (i) or
(ii) of the definition of Change in Control, excluding any merger,
consolidation, conveyance, sale, transfer or lease otherwise constituting a
Change in Control in respect of which at least 90% of the consideration paid
for the Common Stock in that transaction, excluding Cash payments for
fractional shares and Cash payments made pursuant to dissenters’ appraisal
rights, consists of shares of common stock traded on NASDAQ or another U.S.
national or regional securities exchange, or will be so traded immediately
following the merger or consolidation, and, as a result of the merger or
consolidation, the Securities become convertible into such shares of such
common stock.

“Registration Rights
Agreement” means that certain registration rights agreement dated as
of the date of this Indenture between the Company and the Initial
Purchaser and, with respect to any Additional Securities, one or more
registration rights agreements between the Company and the other parties thereto
relating to rights given by the Company to the purchasers of Additional
Securities to register such Additional Securities, or exchange such Additional
Securities for registered Securities under the Securities Act.

“Restricted Global
Security” means a Global Security that is a Transfer Restricted
Security.

“Restricted Security
Legend” means the legend set forth in Section 2.12(a).

“Restricted Stock
Legend” means the legend required by Section 2.12(b).

“Rule 144A”
means Rule 144A under the Securities Act (or any successor provision), as it
may be amended from time to time.

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

“Securities”
means the 0.50% Convertible Senior Notes due October 15, 2011, or any of them
(each, a “Security”).

 5
 

 

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

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

“Significant Subsidiary”
means, in respect of any Person, a Subsidiary of such Person that would
constitute a “significant subsidiary” as such term is defined under
Rule 1-02(w) of Regulation S-X under the Securities Act.

“Subsidiary”
means, in respect of any Person, any corporation, association, partnership or
other business entity of which more than 50% of the total voting power of
shares of Capital Stock or other interests (including partnership interests)
entitled (without regard to the occurrence of any contingency) to vote in the
election of directors, managers, general partners or trustees thereof is at the
time owned or controlled, directly or indirectly, by (i) such Person;
(ii) such Person and one or more Subsidiaries of such Person; or
(iii) one or more Subsidiaries of such Person.

“TIA” means the
Trust Indenture Act of 1939, as amended, and the rules and regulations
thereunder as in effect on the date of this Indenture, except to the extent any
amendment to the Trust Indenture Act expressly provides for application of the
Trust Indenture Act as in effect on another date.

“Trading Day” means a
day on which (i) there is no Market Disruption Event and (ii) NASDAQ or, if the
Common Stock is not listed on NASDAQ, the principal other U.S. national or
regional securities exchange on which the Common Stock is then
listed is open for trading or, if the Common Stock is not so listed, any
Business Day.  A “Trading Day” only
includes those days that have a scheduled closing time of 4:00 p.m. (New York
City time) or the then standard closing time for regular trading on the
relevant exchange or trading system.

“Trading Price” means,
on any date of determination with respect to any Security, the average of the
secondary bid quotations per Security obtained by the Conversion Agent for
$1,000,000 principal amount of Securities at approximately 3:30 p.m., New
York City time, on such determination date from three independent nationally
recognized securities dealers selected by the Company; provided
that, if at least three such bids cannot reasonably be obtained, but two such
bids can reasonably be obtained, then the average of these two bids shall be
used; provided, further, that, if at least two
such bids cannot reasonably be obtained, but one such bid can reasonably be
obtained, this one bid shall be used. 
If, on any date of determination, the Conversion Agent cannot reasonably
obtain at least one bid for $1,000,000 principal amount of the Securities from
an independent nationally recognized securities dealer or, in the reasonable
judgment of the Company, the bid quotations are not indicative of the secondary
market value of the Securities, then the Trading Price of such Securities on
such date of determination will be deemed to be less than 95% of the Conversion
Value.

“Trustee” means
the party named as such in the first paragraph of this Indenture until a
successor replaces it in accordance with the provisions of this Indenture and,
thereafter, means the successor.

 6
 

 

“Trust Officer” shall
mean, when used with respect to the Trustee, any officer within the corporate
trust department of the Trustee, including any vice president, assistant vice
president, assistant secretary, assistant treasurer, trust officer or any other
officer of the Trustee who customarily performs functions similar to those
performed by the Persons who at the time shall be such officers, respectively,
or to whom any corporate trust matter is referred because of such person’s
knowledge of and familiarity with the particular subject and who shall have
direct responsibility for the administration of this Indenture.

“Vice President”,
when used with respect to the Company or the Trustee, means any vice president,
whether or not designated by a number or a word or words added before or after
the title “vice president.”

“Voting Stock” of a
Person means any class or classes of Capital Stock or other interests
(including partnership interests) of such Person then outstanding and normally
entitled (without regard to the occurrence of any contingency) to vote in the
election of directors, managers or trustees thereof.

Section 1.02.   Other Definitions. 

	
  Term

  	
   

  	
  Defined in Section

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
  “Additional
  Securities”

  	
   

  	
  2.16

  	
  (a)

  
	
  “Additional
  Shares”

  	
   

  	
  4.02

  	
  (a)

  
	
  “Agent Members”

  	
   

  	
  2.01

  	
  (b)

  
	
  “Bankruptcy Law”

  	
   

  	
  9.01

  	
   

  
	
  “Change in
  Control”

  	
   

  	
  3.01

  	
  (a)

  
	
  “Closing Sale
  Price Condition”

  	
   

  	
  5.01

  	
  (a)

  
	
  “Company Order”

  	
   

  	
  2.02

  	
   

  
	
  “Conversion
  Agent”

  	
   

  	
  2.03

  	
   

  
	
  “Conversion
  Date”

  	
   

  	
  5.02

  	
   

  
	
  “Conversion
  Notice”

  	
   

  	
  5.02

  	
   

  
	
  “Conversion
  Obligation”

  	
   

  	
  5.05

  	
  (a)

  
	
  “Conversion
  Period”

  	
   

  	
  5.05

  	
  (a)

  
	
  “Conversion Price”

  	
   

  	
  5.06

  	
   

  
	
  “Current Market
  Price”

  	
   

  	
  5.06

  	
  (e)

  
	
  “Custodian”

  	
   

  	
  9.01

  	
   

  
	
  “Daily
  Conversion Value”

  	
   

  	
  5.05

  	
  (a)

  
	
  “Daily Net Share
  Settlement Value”

  	
   

  	
  5.05

  	
  (a)

  
	
  “Depositary”

  	
   

  	
  2.01

  	
  (a)

  
	
  “Dividend
  Adjustment Amount”

  	
   

  	
  5.06

  	
  (e)

  
	
  “DTC”

  	
   

  	
  2.01

  	
  (a)

  
	
  “Effective Date”

  	
   

  	
  4.02

  	
  (b)

  
	
  “Event of
  Default”

  	
   

  	
  9.01

  	
   

  
	
  “Expiration
  Date”

  	
   

  	
  5.06

  	
  (d)

  
	
  “Expiration
  Time”

  	
   

  	
  5.06

  	
  (d)

  
	
  “Fundamental
  Change”

  	
   

  	
  3.01

  	
  (a)

  
	
  “Fundamental
  Change Purchase Date”

  	
   

  	
  3.01

  	
  (a)

  

 7
 

 

 

	
  Term

  	
   

  	
  Defined in Section

  	
   

  	
   

  
	
  “Fundamental
  Change Purchase Notice”

  	
   

  	
  3.01

  	
  (c)

  	
   

  
	
  “Fundamental
  Change Purchase Date”

  	
   

  	
  3.01

  	
  (a)

  	
   

  
	
  “Interest
  Payment Date”

  	
   

  	
  4.01

  	
  (a)

  	
   

  
	
  “Legal Holiday”

  	
   

  	
  13.07

  	
   

  	
   

  
	
  “Liquidated
  Damages Notice”

  	
   

  	
  7.05

  	
   

  	
   

  
	
  “Maximum
  Conversion Rate Adjustment”

  	
   

  	
  4.02

  	
  (g)

  	
   

  
	
  “Paying Agent”

  	
   

  	
  2.03

  	
   

  	
   

  
	
  “Primary
  Registrar”

  	
   

  	
  2.03

  	
   

  	
   

  
	
  “Purchased
  Shares”

  	
   

  	
  5.06

  	
  (d)

  	
   

  
	
  “Quarter”

  	
   

  	
  5.01

  	
  (a)

  	
   

  
	
  “Record Date”

  	
   

  	
  4.01

  	
  (a)

  	
   

  
	
  “Registrar”

  	
   

  	
  2.03

  	
   

  	
   

  
	
  “Resale
  Restriction Termination Date”

  	
   

  	
  2.06

  	
  (a)

  	
   

  
	
  “Rights Plan”

  	
   

  	
  5.06

  	
  (c)

  	
   

  
	
  “Stock Price”

  	
   

  	
  4.02

  	
  (a)

  	
   

  
	
  “Termination of
  Trading”

  	
   

  	
  3.01

  	
  (a)

  	
   

  
	
  “Transfer
  Restricted Securities”

  	
   

  	
  2.12

  	
  (a)

  	
   

  
	
  “Transforming
  Transaction”

  	
   

  	
  5.01

  	
  (b)

  	
   

  
	
  “Trigger Event”

  	
   

  	
  5.06

  	
  (c)

  	
   

  
	
  “Triggering
  Distribution”

  	
   

  	
  5.06

  	
  (d)

  	
   

  
	
  “Unissued
  Shares”

  	
   

  	
  3.01

  	
  (a)

  	
   

  
	
  “Volume Weighted
  Average Price”

  	
   

  	
  5.05

  	
  (a)

  	
   

  

 

Section   1.03.   Trust Indenture Act Provisions.

Whenever this Indenture
refers to a provision of the TIA, that provision is incorporated by reference
in and made a part of this Indenture. 
The Indenture shall also include those provisions of the TIA required to
be included herein by the provisions of the Trust Indenture Reform Act of
1990.  The following TIA terms used in
this Indenture have the following meanings:

“indenture securities” means the Securities;

“indenture trustee” means the Trustee; and

“obligor” on the Securities means the
Company or any other obligor on the Securities.

All other terms used in
this Indenture that are defined in the TIA, defined by TIA reference to another
statute or defined by any SEC rule and not otherwise defined herein have
the meanings assigned to them therein.

Section 1.04.   Rules of Construction.

Unless the context
otherwise requires:

 8

 

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

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

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

(D)  provisions apply to successive
events and transactions;

(E)  the term “merger” includes a
statutory share exchange, and the term “merged” has a correlative meaning;

(F)  the masculine gender includes
the feminine and the neuter;

(G)  references to agreements and
other instruments include subsequent amendments thereto;

(H)  “herein,” “hereof” and other
words of similar import refer to this Indenture as a whole and not to any
particular Article, Section or other subdivision; and

(I)  references to the payments on
the Securities shall include Liquidated Damages payable hereunder and under the
Registration Rights Agreement, if any.

ARTICLE 2 THE SECURITIES

Section 2.01.   Form and Dating.

The Securities and the corresponding Trustee’s
certificate of authentication shall be substantially in the respective form set
forth in Exhibit A, which Exhibit is incorporated in an made part of
this Indenture. The Securities may have notations, legends or endorsements
required by law, stock exchange rule or usage. The Company shall provide any
such notations, legents or endorsements ro the Trustee in writing. The
Securities shall be dated the date of their authentication.

(a)   Restricted Global Securities.   Securities
offered and sold to QIBs in reliance on Rule 144A and resold to IAIs in the
United States of America shall be issued in the form of one or more Restricted
Global Securities, substantially in the form of Exhibit A, which shall be
deposited on behalf of the acquirers of the Securities represented thereby with
the Trustee, at its Corporate Trust Office, as custodian for the depositary,
The Depository Trust Company (“DTC”) (such
depositary, or any successor thereto, being hereinafter referred to as the “Depositary”), and registered in the name of its nominee,
Cede & Co., duly executed by the Company and authenticated by the
Trustee as hereinafter provided.  The aggregate principal amount of the
Global Securities may from time to time be increased or decreased by
adjustments made on the records of the Securities Custodian as hereinafter
provided, subject in each case to compliance with the Applicable Procedures.

(b)   Global Securities in General.   Each
Global Security shall represent such of the outstanding Securities as shall be
specified therein, and each shall provide that it shall represent 

 9
 

 

the aggregate amount of
outstanding Securities from time to time endorsed thereon and that the
aggregate amount of outstanding Securities represented thereby may from time to
time be reduced or increased, as appropriate, to reflect exchanges,
redemptions, purchases or conversions of such Securities.  Any adjustment
of the aggregate principal amount of a Global Security to reflect the amount of
any increase or decrease in the amount of outstanding Securities represented
thereby shall be made by the Trustee in accordance with instructions given by
the Holder thereof as required by Section 2.12 hereof and shall be made on
the records of the Trustee and the Depositary.

Members of, or participants in, the Depositary (“Agent Members”) shall have no rights under this Indenture with
respect to any Global Security held on their behalf by the Depositary or under
the Global Security, and the Depositary (including, for this purpose, its
nominee) may be treated by the Company, the Trustee and any agent of the
Company or the Trustee as the absolute owner and Holder of such Global Security
for all purposes whatsoever.  Notwithstanding the foregoing, nothing
herein shall (A) prevent the Company, the Trustee or any agent of the
Company or the Trustee from giving effect to any written certification, proxy
or other authorization furnished by the Depositary or (B) impair, as
between the Depositary and its Agent Members, the operation of customary
practices governing the exercise of the rights of a Holder of any Security.

(c)   Book Entry Provisions.   The
Company shall execute and the Trustee shall, in accordance with this
Section 2.01(c) and Section 2.02, authenticate and deliver
initially one or more Global Securities that (i) shall be registered in
the name of Cede & Co. or as otherwise instructed by the Depositary,
(ii) shall be delivered by the Trustee to the Depositary or pursuant to
the Depositary’s instructions and (iii) shall bear legends substantially
to the following effect:

“UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED
REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”),
TO UNITED THERAPEUTICS CORPORATION (THE “COMPANY”) OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR
PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF
CEDE & CO. OR IN 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 2.02.   Execution and Authentication.

An Officer shall sign the Securities for the Company
by manual or facsimile signature.  Typographic and other minor errors or
defects in any such facsimile signature shall not affect the validity or
enforceability of any Security which has been authenticated and delivered by
the Trustee.

If an Officer whose signature is on a Security no
longer holds that office at the time the Trustee authenticates the Security,
the Security shall be valid nevertheless.

 10
 

 

 

A Security shall not be valid until an authorized
signatory of the Trustee manually or by facsimile signs the certificate of
authentication on the Security.  The signature shall be conclusive
evidence that the Security has been authenticated under this Indenture.

The Trustee shall authenticate and make available for
delivery Securities for original issue in the aggregate principal amount of up
to $250,000,000 upon receipt of (i) a written order or orders of the
Company signed by two Officers of the Company (a “Company Order”) and
delivered to the Trustee, and (ii) an Officers’ Certificate and Opinion of
Counsel pursuant to Section 13.04 hereof; provided that
additional Securities may be issued pursuant to Section 2.16.  Each
Company Order shall specify the amount of Securities to be authenticated, shall
provide that all Securities will be represented by a Global Security and the
date on which each original issue of Securities is to be authenticated.  The Trustee shall have the right to decline
to authenticate and deliver any Securities under this Section if the Trustee,
being advised by counsel, determines that such action may not lawfully be taken
or if the Trustee in good faith shall determine that such action would expose
the Trustee to personal liability to existing Holders.

The Trustee shall act as the initial authenticating
agent.  Thereafter, the Trustee may appoint an authenticating agent
acceptable to the Company to authenticate Securities.  An authenticating
agent may authenticate Securities whenever the Trustee may do so.  Each
reference in this Indenture to authentication by the Trustee includes
authentication by such agent.  An authenticating agent shall have the same
rights as an Agent to deal with the Company or an Affiliate of the Company.

The Securities shall be issuable only in registered
form without coupons and only in denominations of $1,000 principal amount and
any integral multiple thereof.

Section 2.03.   Registrar, Paying Agent and
Conversion Agent.

The Company shall maintain one or more offices or
agencies where Securities may be presented for registration of transfer or for
exchange (each, a “Registrar”),
one or more offices or agencies where Securities may be presented for payment
(each, a “Paying Agent”), one or more offices or
agencies where Securities may be presented for conversion (each, a “Conversion Agent”) and one or more offices or agencies where notices
and demands to or upon the Company in respect of the Securities and this
Indenture may be served.  One of the
Registrars (the “Primary Registrar”) shall keep a register
of the Securities and of their transfer and exchange.

The Company shall enter into an appropriate agency
agreement with any Agent not a party to this Indenture.  The agreement
shall implement the provisions of this Indenture that relate to such
Agent.  The Company shall notify the Trustee in writing of the name and
address of any Agent not a party to this Indenture.  If the Company fails
to maintain a Registrar, Paying Agent, or Conversion Agent, or fails to give
the foregoing notice, the Trustee shall act as such.  The Company or any
Affiliate of the Company may act as Paying Agent (except for the purposes of
Article 11).

 11
 

 

 

The Company hereby initially designates the Trustee as
Paying Agent, Registrar, Securities Custodian and Conversion Agent, and the
Corporate Trust Office of the Trustee to be such office or agency of the
Company for each of the aforesaid purposes.

Section 2.04.   Paying Agent to Hold Money in Trust.

Prior to 11:00 a.m., New York City time, on each
due date of the principal of, premium on, if any, or interest on, any
Securities, the Company shall deposit with a Paying Agent a sum sufficient to
pay such principal, premium on, if any, and interest so becoming due.  The
Company shall require each Paying Agent other than the Trustee to agree in
writing that such Paying Agent shall hold in trust for the benefit of Holders
or the Trustee all money held by the Paying Agent for the payment of principal
of, premium on, if any, or interest on, the Securities and shall notify the
Trustee in writing of any default by the Company (or any other obligor on the
Securities) in making any such payment.  If the Company or an Affiliate of
the Company acts as Paying Agent, it shall, before 11:00 a.m., New York
City time, on each due date of the principal of, premium on, if any, or
interest on, any Securities, segregate the money and hold it as a separate
trust fund.  The Company at any time may require a Paying Agent to pay all
money held by it to the Trustee, and the Trustee may at any time during the
continuance of any default, upon written request to a Paying Agent, require
such Paying Agent to pay forthwith to the Trustee all sums so held in trust by
such Paying Agent.  Upon doing so, the Paying Agent (other than the
Company) shall have no further liability for the money.

Section 2.05.   Securityholder 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 Holders.  If the Trustee is
not the Primary Registrar, the Company shall furnish to the Trustee at least
five Business Days before each semiannual 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 Holders.

Section 2.06.   Transfer and Exchange.

(a)           The following provision shall apply
with respect to any proposed transfer of a Security prior to the date which is
two years after the later of the date of its original issue and the last date
on which the Company or any Affiliate of the Company was the owner of such
Securities (or any predecessor thereto) (the “Resale
Restriction Termination Date”):

(i) a transfer of a Security in certificated form
to a QIB shall be made upon receipt by the Trustee or its agent of a
certificate substantially in the Form of Certificate to be Delivered Upon
Exchange or Registration of Transfer of Securities set forth on the reverse of
the Security that the transferee is purchasing the Security for its own account
or an account with respect to which it exercises sole investment discretion and
that it and any such account is a “qualified institutional buyer” within the
meaning of Rule 144A, and is aware that the sale to it is being made in
reliance on Rule 144A and acknowledges that it has received such information
regarding the Company as it has requested pursuant to Rule 144A or has
determined not to request such information and that it is aware 

 12
 

 

that the transferor is
relying upon its foregoing representations in order to claim the exemption from
registration provided by Rule 144A; and

(ii) a transfer
of a Security or a beneficial interest therein pursuant to an exemption from
registration under the Securities Act other than Rule 144A shall be made upon
receipt by the Registrar and the Company of such opinions of counsel,
certificates and/or other information reasonably required by and satisfactory
to them in order to ensure compliance with the Securities Act, including, in
the case of a transfer of a Security or a beneficial interest therein to an IAI,
a certificate substantially in the form set forth in Section 2.14 from the
proposed transferee.

(b)           Subject to compliance with any
applicable additional requirements contained in Section 2.12, when a
Security is presented to a Registrar with a request to register a transfer
thereof or to exchange such Security for an equal principal amount of
Securities of other authorized denominations, the Registrar shall register the
transfer or make the exchange as requested; provided, however, that
every Security presented or surrendered for registration of transfer or
exchange shall be duly endorsed or accompanied by an assignment form and, if
applicable, a transfer certificate, each in the form included in Exhibit A,
and in form satisfactory to the Registrar duly executed by the Holder thereof
or its attorney duly authorized in writing. 
Upon the transfer, exchange or replacement of Securities not bearing a
Restricted Security Legend, the Registrar shall deliver Securities that do not
bear a Restricted Security Legend.  Upon
the transfer, exchange or replacement of Securities bearing a Restricted
Security Legend, the Registrar shall deliver only Securities that bear such
Restricted Security Legend unless (i) a Security is being transferred pursuant
to an effective registration statement, (ii) such Securities (or beneficial
interests) are transferred, replaced or exchanged on or after the Resale
Restriction Termination Date or (iii) if requested by the Company or Registrar,
there is delivered to the Company and the Registrar an Opinion of Counsel to
the effect that neither such legend nor the related restrictions on transfer
are required in order to maintain compliance with the provisions of the
Securities Act.  The Restricted Security Legend on any Security shall be removed
at the request of the Holder on or after the Resale Restriction Termination
Date therefor.  To permit registration of
transfers and exchanges, upon surrender of any Security for transfer or
exchange at an office or agency maintained pursuant to Section 2.03, the
Company shall execute and the Trustee shall authenticate Securities of a like
aggregate principal amount at the Registrar’s request.  Any exchange or
transfer shall be without charge, except that the Company or the Registrar may
require payment of a sum sufficient to cover any tax or other governmental
charge that may be imposed in relation thereto; provided
that this sentence shall not apply to any exchange pursuant to
Section 2.10, 3.04, 5.02 (last paragraph) or 12.05.

None of the Company, any
Registrar or the Trustee shall be required to exchange or register a transfer
of any Securities or portions thereof in respect of which a Fundamental Change
Purchase Notice has been delivered and not withdrawn by the Holder thereof
(except, in the case of the purchase of a Security in part, the portion thereof
not to be purchased).

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

 13
 

 

 

(c)           Any Registrar appointed pursuant to
Section 2.03 hereof shall provide to the Trustee such information as the
Trustee may reasonably require in connection with the delivery by such
Registrar of Securities upon transfer or exchange of Securities.

(d)           Each Holder of a Security agrees to
indemnify the Company and the Trustee against any liability that may result
from the transfer, exchange or assignment of such Holder’s Security in
violation of any provision of this Indenture and/or applicable U.S. federal or
state securities law. Prior to the due presentment of a registration of a
transfer of any Security, the Trustee, any Agent and the Company may deem and
treat the Person in whose name any Security is registered as the absolute owner
of such Security for the purpose of all payments with respect to such
Securities, and neither the Trustee, any Agent nor the Company shall be
affected by notice to the contrary. Neither the Trustee nor any Agent shall
have any responsibility for any actions taken or not taken by the Depositary.

The Trustee shall have no obligation or duty to
monitor, determine or inquire as to compliance with any restrictions on
transfer imposed under this Indenture or under applicable law with respect to
any transfer of any interest in any Security (including any transfers between
or among Agent Members or other beneficial owners of interests in any Global
Security) other than to require delivery of such certificates and other
documentation or evidence as are expressly required by, and to do so if and
when expressly required by the terms of, this Indenture and to examine the same
to determine substantial compliance as to form with the express requirements
hereof.

Section 2.07.   Replacement Securities.

If any mutilated Security is surrendered to the
Company, a Registrar or the Trustee, or the Company, a Registrar and the
Trustee receive evidence to their satisfaction of the destruction, loss or
theft of any Security, and there is delivered to the Company, the applicable
Registrar and the Trustee such security or indemnity as will be required by
them to save each of them harmless, then, in the absence of written notice to
the Company, such Registrar or the Trustee that such Security has been acquired
by a bona fide purchaser, the Company shall execute, and upon its written
request the Trustee shall authenticate and deliver, in exchange for any such
mutilated Security or in lieu of any such destroyed, lost or stolen Security, a
new Security of like tenor and principal amount, bearing a number not
contemporaneously outstanding.

In case any such mutilated, destroyed, lost or stolen
Security has become or is about to become due and payable, or is about to be
redeemed or purchased by the Company pursuant to Article 3, the Company in
its discretion may, instead of issuing a new Security, pay, redeem or purchase
such Security, as the case may be.

Upon the issuance of any new Securities under this
Section 2.07, the Company may require the payment of a sum sufficient to
cover any tax or other governmental charge that may be imposed in relation
thereto and any other reasonable expenses (including the reasonable fees and
expenses of the Trustee or the Registrar) in connection therewith.

Every new Security issued pursuant to this
Section 2.07 in lieu of any mutilated, destroyed, lost or stolen Security
shall constitute an original additional contractual obligation of 

 14
 

 

the Company, whether or
not the mutilated, destroyed, lost or stolen Security shall be at any time
enforceable by anyone, and shall be entitled to all benefits of this Indenture
equally and proportionately with any and all other Securities duly issued
hereunder.

The provisions of this Section 2.07 are (to the
extent lawful) exclusive and shall preclude (to the extent lawful) all other
rights and remedies with respect to the replacement or payment of mutilated,
destroyed, lost or stolen Securities.

Section 2.08.   Outstanding Securities.

Securities outstanding at any time are all Securities
authenticated by the Trustee, except for those canceled by it, those converted
pursuant to Article 5, those delivered to it for cancellation or
surrendered for transfer or exchange and those described in this
Section 2.08 as not outstanding.

If a Security is replaced pursuant to
Section 2.07, it ceases to be outstanding unless the Company receives,
subsequent to the new Security’s authentication, proof satisfactory to the
Company that the replaced Security is held by a bona fide purchaser unaware
that such Security has been replaced.

If a Paying Agent (other than the Company or an
Affiliate of the Company) holds in respect of Securities on a Fundamental
Change Purchase Date or the Final Maturity Date money sufficient to pay the
principal of (including premium, if any), and any accrued interest on
Securities (or portions thereof) payable on that date, then on and after such
Fundamental Change Purchase Date or the Final Maturity Date, as the case may
be, such Securities (or portions thereof, as the case may be) shall cease to be
outstanding and any interest on them shall cease to accrue.

Subject to the restrictions contained in
Section 2.09, a Security does not cease to be outstanding because the
Company or an Affiliate of the Company holds the Security.

Section 2.09.   Treasury Securities.

In determining whether the Holders of the required
principal amount of Securities have concurred in any notice, direction, waiver
or consent, Securities owned by the Company or any other obligor on the
Securities or by any Affiliate of the Company or of such other obligor shall be
disregarded, except that, for purposes of determining whether the Trustee shall
be protected in relying on any such notice, direction, waiver or consent, only
Securities which a Trust Officer of the Trustee actually knows are so owned
shall be so disregarded.  Securities so owned which have been pledged in
good faith shall not be disregarded if the pledgee establishes to the satisfaction
of the Trustee the pledgee’s right so to act with respect to the Securities and
that the pledgee is not the Company or any other obligor on the Securities or
any Affiliate of the Company or of such other obligor.

 15
 

 

Section 2.10.   Temporary Securities.

Until definitive Securities are ready for delivery,
the Company may prepare and execute, and, upon receipt of a Company Order, the
Trustee shall authenticate and deliver, temporary Securities.  Temporary
Securities shall be substantially in the form of definitive Securities but may
have variations that the Company considers appropriate for temporary Securities
and as shall be reasonably acceptable to the Trustee.  Every temporary Security will be executed and
registered by the Company and be authenticated by the Trustee upon the same
conditions and in substantially the same manner, and with like effect, as the
definitive Securities. Without unreasonable delay, the Company shall prepare
and the Trustee shall authenticate and deliver definitive Securities in
exchange for temporary Securities.

Section 2.11.   Cancellation.

The Company at any time may deliver Securities to the
Trustee for cancellation.  The Registrar, the Paying Agent and the
Conversion Agent shall forward to the Trustee or its agent any Securities
surrendered to them for transfer, exchange, redemption, payment or
conversion.  The Trustee and no one else shall cancel, in accordance with
its standard procedures, all Securities surrendered for transfer, exchange,
redemption, payment, conversion or cancellation and shall deliver the canceled
Securities to the Company.  All Securities which are redeemed, purchased
or otherwise acquired by the Company or any of its Subsidiaries prior to the
Final Maturity Date shall be delivered to the Trustee for cancellation, and the
Company may not hold or resell such Securities or issue any new Securities to
replace any such Securities or any Securities that any Holder has converted
pursuant to Article 5.

Section 2.12.   Legends; Additional Transfer
Requirements.

(a)  Every
Security that bears or is required under this Section 2.12(a) to bear the
Restricted Security Legend set forth in this Section 2.12(a) (the “Transfer Restricted Securities”) shall be
subject to the restrictions on transfer set forth in Section 2.06 and this
Section 2.12(a) (including those set forth in the Restricted Security Legend
set forth below), and the Holder of each such Transfer Restricted Security, by
such Holder’s acceptance thereof, agrees to be bound by all such restrictions
on transfer.  As used in Sections 2.12(a)
and 2.12(b), the term “transfer” includes any sale, pledge, transfer or other
disposition whatsoever of any Transfer Restricted Security.  The Registrar shall not register any transfer
of a Transfer Restricted Security not made in accordance with the restrictions
on transfer set forth in Section 2.06 and this Section 2.12.

Subject to the last paragraph of this Section 2.12(a)
and Section 2.15 with respect to Common Stock, prior to the Resale Restriction
Termination Date, any certificate evidencing any Security (and all securities
issued in exchange therefor or substitution thereof; including Common Stock, if
any, issued upon conversion thereof, which shall bear the legend set forth in
Section 2.12(b), if applicable) shall bear a legend in substantially the
following form:

“THIS SECURITY AND THE SHARES OF UNITED THERAPEUTICS
CORPORATION (THE “COMPANY”) COMMON STOCK (“COMMON STOCK”) ISSUABLE UPON
CONVERSION OF THIS SECURITY HAVE

 16
 

 

 NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”),
OR ANY STATE SECURITIES LAWS.  NEITHER
THIS SECURITY, THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS
SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN OR THEREIN MAY BE REOFFERED,
SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN
THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR
NOT SUBJECT TO, REGISTRATION.

THE HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE HEREOF,
AGREES TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE
(THE “RESALE RESTRICTION TERMINATION DATE”) THAT IS TWO YEARS AFTER THE LATER
OF THE ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE COMPANY OR ANY
AFFILIATE OF THE COMPANY WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF
SUCH SECURITY) ONLY (A) TO THE COMPANY OR ANY SUBSIDIARY THEREOF, (B) FOR SO
LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A, TO A
PERSON IT REASONABLY BELIEVES IS A “QUALIFIED INSTITUTIONAL BUYER” AS DEFINED
IN RULE 144A UNDER THE SECURITIES ACT THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR
THE ACCOUNT OF A QUALIFIED INSTITUTIONAL BUYER TO WHICH NOTICE IS GIVEN THAT
THE TRANSFER IS BEING MADE IN RELIANCE ON RULE 144A, (C) PURSUANT TO A
REGISTRATION STATEMENT THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES
ACT, OR (D) PURSUANT TO ANOTHER AVAILABLE EXEMPTION FROM THE REGISTRATION
REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO THE RIGHTS OF THE COMPANY AND
THE WITHIN MENTIONED TRUSTEE PRIOR TO ANY SUCH OFFER, SALE OR TRANSFER PURSUANT
TO CLAUSE (D) TO REQUIRE THE DELIVERY OF AN OPINION OF COUNSEL, CERTIFICATION
AND/OR OTHER INFORMATION SATISFACTORY TO EACH OF THEM, AND IN EACH OF THE
FOREGOING CASES WHERE REGISTRATION OR TRANSFER OF THIS SECURITY IS REQUIRED, A
CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON THE OTHER SIDE OF THIS
SECURITY COMPLETED AND DELIVERED BY THE TRANSFEROR TO THE TRUSTEE.  THIS LEGEND WILL BE REMOVED ON OR AFTER THE
RESALE RESTRICTION TERMINATION DATE UPON THE REQUEST OF THE HOLDER THEREFOR.”

Any Security (or security issued in exchange or
substitution therefor) as to which such restrictions on transfer shall have
expired in accordance with their terms or that has been transferred, replaced
or exchanged on or after the Resale Restriction Termination Date or that has
been transferred pursuant to a registration statement that has been declared
effective under 

 17

 

the Securities Act may, upon surrender of such
Security to the Registrar for exchange in accordance with the provisions of
this Section 2.12, be exchanged for a new Security or Securities, of like tenor
and aggregate principal amount, which shall not bear the Restricted Security
Legend required by this Section 2.12(a).

(b)  Every stock
certificate representing Common Stock issued upon conversion of a Transfer
Restricted Security that bears or is required under this Section 2.12(b) to
bear the Restricted Stock Legend set forth in this Section 2.12(b) shall be
subject to the restrictions on transfer set forth in Section 2.06 and this
Section 2.12(b) (including those set forth in the Restricted Stock Legend set
forth below), and the Holder of such Common Stock issued upon conversion of a
Transfer Restricted Security, by such Holder’s acceptance thereof, agrees to be
bound by all such restrictions on transfer and the further restrictions set
forth in Section 2.15.  The Company shall
not register any transfer of Common Stock issued upon conversion of such a
Transfer Restricted Security not made in accordance with the restrictions on
transfer set forth in this Section 2.12.

Subject to the last paragraph of this Section 2.12(b)
and Section 2.15 with respect to Common Stock, prior to the Resale Restriction
Termination Date, any stock certificate representing Common Stock issued upon
conversion of a Transfer Restricted Security shall bear a legend in
substantially the following form, unless such Common Stock has been sold
pursuant to a registration statement that has been declared effective under the
Securities Act (and which continues to be effective at the time of such
issuance) or such Common Stock has been issued upon conversion of Securities
that have been transferred pursuant to a registration statement that has been
declared effective under the Securities Act:

“THIS SECURITY (OR ITS PREDECESSOR) WAS ORIGINALLY
ISSUED IN A TRANSACTION EXEMPT FROM REGISTRATION UNDER THE SECURITIES ACT OF
1933, AS AMENDED (THE “SECURITIES ACT”), OR ANY STATE SECURITIES LAWS.  NEITHER THIS SECURITY NOR ANY INTEREST OR
PARTICIPATION HEREIN MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED,
ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR
UNLESS SUCH TRANSACTION IS EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION.

THE HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE HEREOF,
AGREES TO OFFER, SELL OR OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE
(THE “RESALE RESTRICTION TERMINATION DATE”) THAT IS TWO YEARS AFTER THE LATER
OF THE ORIGINAL ISSUE DATE HEREOF AND THE LAST DATE ON WHICH THE COMPANY OR ANY
AFFILIATE OF THE COMPANY WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF
SUCH SECURITY) ONLY (A) TO THE COMPANY OR ANY SUBSIDIARY THEREOF, (B) FOR SO
LONG AS THE SECURITIES ARE ELIGIBLE FOR RESALE PURSUANT TO RULE 144A, TO A
PERSON IT REASONABLY BELIEVES IS A “QUALIFIED INSTITUTIONAL BUYER” AS DEFINED
IN RULE 144A UNDER THE SECURITIES ACT THAT PURCHASES FOR ITS 

 18
 

 

OWN ACCOUNT OR FOR THE ACCOUNT OF A QUALIFIED INSTITUTIONAL
BUYER TO WHICH NOTICE IS GIVEN THAT THE TRANSFER IS BEING MADE IN RELIANCE ON
RULE 144A, (C) PURSUANT TO A REGISTRATION STATEMENT THAT HAS BEEN DECLARED
EFFECTIVE UNDER THE SECURITIES ACT, OR (D) PURSUANT TO ANOTHER AVAILABLE
EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT TO
THE RIGHTS OF THE COMPANY AND THE WITHIN MENTIONED TRUSTEE PRIOR TO ANY SUCH
OFFER, SALE OR TRANSFER PURSUANT TO CLAUSE (D) TO REQUIRE THE DELIVERY OF AN
OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH
OF THEM, AND IN EACH OF THE FOREGOING CASES WHERE REGISTRATION OR TRANSFER OF
THIS SECURITY IS REQUIRED, A CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON
THE OTHER SIDE OF THIS SECURITY COMPLETED AND DELIVERED BY THE TRANSFEROR TO
THE TRUSTEE.  THIS LEGEND WILL BE REMOVED
ON OR AFTER THE RESALE RESTRICTION TERMINATION DATE UPON THE REQUEST OF THE
HOLDER THEREFOR.”

Any stock
certificate (or security issued in exchange or substitution therefor) as to
which such restrictions on transfer shall have expired in accordance with their
terms or that has been transferred, replaced or exchanged on or after the
Resale Restriction Termination Date or that has been transferred pursuant to a
registration statement that has been declared effective under the Securities
Act may, upon surrender of such stock certificate to the Registrar for exchange
in accordance with the provisions of this Section 2.12 and Section 2.15, be
exchanged for a new stock certificate, of like tenor and aggregate number of
shares, which shall not bear the Restricted Stock Legend required by this
Section 2.12(b).

(c)  Any Security
or Common Stock issued upon the conversion or exchange of a Security that,
prior to the expiration of the holding period applicable to sales thereof under
Rule 144(k) under the Securities Act (or any successor provision), is purchased
or owned by the Company or any Affiliate thereof may not be resold by the
Company or such Affiliate unless registered under the Securities Act or resold
pursuant to an exemption from the registration requirements of the Securities
Act in a transaction that results in such Security or Common Stock, as the case
may be, no longer being “restricted securities” (as defined under Rule 144).

(d)  Notwithstanding
any provision of Section
2.06 and Section 2.12 to the contrary, in the event Rule
144(k) as promulgated under the Securities Act (or any successor rule) is
amended to change the two-year period under Rule 144(k) (or the corresponding
period under any successor rule), from and after receipt by the Trustee of the
Officers’ Certificate and Opinion of Counsel provided for in this Section 2.12(d),
(i) each reference in Section 2.12(a) to “two years”
and in the restrictive legend set forth in such paragraph to “TWO YEARS” shall
be deemed for all purposes hereof to be references to such changed period, (ii)
each reference in Section 2.12(b) to “two years” and in the
restrictive legend set forth in such paragraph to “TWO YEARS” shall be deemed
for all purposes hereof to be references to such changed period and (iii) all
corresponding references in the Security (including the definition of Resale
Restriction 

 19
 

 

Termination Date) and the restrictive legends thereon
shall be deemed for all purposes hereof to be references to such changed
period, provided that such
changes shall not become effective if they are otherwise prohibited by, or
would otherwise cause a violation of, the then-applicable federal securities
laws.  The provisions of this Section 2.12(d)
will not be effective until such time as the Opinion of Counsel and Officers’
Certificate have been received by the Trustee hereunder.  This Section 2.12(d) shall apply to
successive amendments to Rule 144(k) (or any successor rule) changing the
holding period thereunder.

(e)  A Global
Security may not be transferred, in whole or in part, to any Person other than
the Depositary or a nominee or any successor thereof, and no such transfer to
any such other Person may be registered; provided that
the foregoing shall not prohibit any transfer of a Security that is issued in
exchange for a Global Security but is not itself a Global Security.  No
transfer of a Security to any Person shall be effective under this Indenture or
the Securities unless and until such Security has been registered in the name
of such Person.  Notwithstanding any other provisions of this Indenture or
the Securities, transfers of a Global Security, in whole or in part, shall be
made only in accordance with this Section 2.12.

(f)  The
provisions of clauses (i), (ii), (iii) and (iv) below shall apply
only to Global Securities:

(i)  Notwithstanding
any other provisions of this Indenture or the Securities, a Global Security
shall not be exchanged in whole or in part for a Security registered in the
name of any Person other than the Depositary or one or more nominees thereof; provided that a Global Security may be exchanged for
Securities registered in the names of any person designated by the Depositary
in the event that (A) the Depositary has notified the Company that it is
unwilling or unable to continue as Depositary for such Global Security or such
Depositary has ceased to be a “clearing agency” registered under the Exchange
Act, and a successor Depositary is not appointed by the Company within 90 days
or (B) an Event of Default has occurred and is continuing with
respect to the Securities.  Any Global
Security exchanged pursuant to clause (A) shall be so exchanged in whole and
not in part, and any Global Security exchanged pursuant to clause (B) above
may be exchanged in whole or from time to time in part as directed by the
Depositary.  Any Security issued in
exchange for a Global Security or any portion thereof shall be a Global
Security; provided that any such Security so
issued that is registered in the name of a Person other than the Depositary or
a nominee thereof shall not be a Global Security.

(ii)  Securities
issued in exchange for a Global Security or any portion thereof shall be issued
in definitive, fully registered form, without interest coupons, shall have an
aggregate principal amount equal to that of such Global Security or portion
thereof to be so exchanged, shall be registered in such names and be in such
authorized denominations as the Depositary shall designate and shall bear the
applicable legends provided for herein.  Any Global Security to be
exchanged in whole shall be surrendered by the Depositary to the Trustee, as
Registrar.  With regard to any Global Security to be exchanged in part,
either such Global Security shall be so surrendered for exchange or, if the
Trustee is acting as custodian for the Depositary or its nominee with respect
to such Global Security, the principal amount thereof shall be reduced by an
amount equal to the portion thereof to be so exchanged, by means of an
appropriate adjustment made on the 

 20
 

 

records of the
Trustee.  Upon any such surrender or adjustment, the Trustee shall
authenticate and deliver the Security issuable on such exchange to or upon the
order of the Depositary or an authorized representative thereof.

(iii)  The
registered Holder may grant proxies and otherwise authorize any Person,
including Agent Members and persons that may hold interests through Agent
Members, to take any action which a Holder is entitled to take under this
Indenture or the Securities.

(iv)  In the
event of the occurrence of any of the events specified in clause
(i) above, the Company will promptly make available to the Trustee a
reasonable supply of Certificated Securities in definitive, fully registered
form, without interest coupons.

Section 2.13.   Cusip or ISIN Numbers.

The Company in issuing the Securities may use one or
more “CUSIP” and/or ISIN numbers (if then generally in use), and, if so, the
Trustee shall use “CUSIP” and/or ISIN numbers in notices of purchase 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 Securities or as contained in any
notice of a purchase and that reliance may be placed only on the other identification
numbers printed on the Securities, and any such purchase shall not be affected
by any defect in or omission of such numbers.  The Company will promptly
notify the Trustee in writing of any change in the “CUSIP” and/or ISIN numbers.

Section 2.14.   Form of Certificate To Be Delivered
in Connection with Transfers to Institutional Accredited Investors.

[Date]

United Therapeutics Corporation

c/o The Bank of New York, as Trustee

101 Barclay Street, Floor 8W

New York, New York 10286

Attention:  Corporate Trust
Administration

Ladies and Gentlemen:

This certificate is delivered to request a transfer of
$__________ principal amount of the 0.50% Convertible Senior Notes due October
15, 2011 (the “Securities”) of United Therapeutics Corporation (the “Company”).

Upon transfer, the
Securities would be registered in the name of the new beneficial owner as
follows:

	
  Name:

  	
   

  
	
  Address:

  	
   

  
	
  Taxpayer ID
  Number:

  	
   

  

 

 21
 

 

The undersigned represents and warrants to you that:

1.  We are an
institutional accredited investor (as defined in Rule 501(a)(1), (2), (3) or
(7) under the Securities Act of 1933, as amended (the “Securities Act”)) purchasing
for our own account or for the account of such an institutional accredited
investor at least $250,000 principal amount of the Securities, and we are
acquiring the Securities not with a view to, or for offer or sale in connection
with, any distribution in violation of the Securities Act.  We have such knowledge and experience in
financial and business matters as to be capable of evaluating the merits and
risk of our investment in the Securities and we invest in or purchase
securities similar to the Securities in the normal course of our business.  We and any accounts for which we are acting
are each able to bear the economic risk of the complete loss of our or its
investment.

2. We understand
that the Securities have not been registered under the Securities Act and,
unless so registered, may not be sold except as permitted in the following
sentence.  We agree on our own behalf and
on behalf of any investor account for which we are purchasing Securities to
offer, sell or otherwise transfer such Securities prior to the date that is two
years after the later of the date of original issue and the last date on which
the Company or any affiliate of the Company was the owner of such Securities
(or any predecessor thereto) (the “Resale Restriction Termination Date”) only
(a) to the Company, (b) pursuant to a registration statement which has been
declared effective under the Securities Act, (c) in a transaction complying
with the requirements of Rule 144A under the Securities Act (“Rule 144A”), to a
Person we reasonably believe is a qualified institutional buyer under Rule 144A
(a “QIB”) that purchases for its own account or for the account of a QIB and to
whom notice is given that the transfer is being made in reliance on Rule 144A,
(d) to an institutional accredited investor within the meaning of Rule
501(a)(1), (2), (3) or (7) under the Securities Act that is purchasing for its own
account or for the account of such an institutional accredited investor, in
each case in a minimum principal amount of Securities of $250,000 or (e)
pursuant to another available exemption from the registration requirements of
the Securities Act, subject in each of the foregoing cases to compliance with
any applicable state securities laws. 
The foregoing restrictions on resale will not apply subsequent to the
Resale Restriction Termination Date.  If
any resale or other transfer of the Securities is proposed to be made pursuant
to clause (d) above prior to the Resale Restriction Termination Date, the
transferor shall deliver a letter from the transferee substantially in the form
of this letter to the Company and the Trustee, which shall provide, among other
things, that the transferee is an institutional accredited investor (within the
meaning of Rule 501(a)(1), (2), (3) or (7) under the Securities Act) and that
it is acquiring such Securities for investment purposes and not for
distribution in violation of the Securities Act.  Each purchaser acknowledges that the Company
and the Trustee reserve the right prior to any offer, sale or other transfer
prior to the Resale Restriction Termination Date of the Securities pursuant to
clauses (d) or (e) above to require the delivery of an opinion of counsel,
certifications and/or other information satisfactory to the Company and the Trustee.

	
  

  	
  TRANSFEREE:

  	
   

  
	
   

  	
  BY:

  	
   

  

 

 22
 

 

Section 2.15.   Issuance, Transfer and Exchange of
Common Stock Issuable Upon Conversion of the Securities.

Shares of Common Stock to be issued upon conversion of
Securities prior to the effectiveness of an applicable registration statement
under the Securities Act shall be physically delivered in certificated form to
the Holders converting such Securities and the certificate representing such
shares of Common Stock shall bear the Restricted Stock Legend unless removed in
accordance with Section 2.12(b).

If (i) shares of Common Stock to be issued upon
conversion of Securities prior to the effectiveness of an applicable
registration statement under the Securities Act are to be registered in a name
other than that of the Holder of such Securities or (ii) shares of Common Stock
represented by a certificate bearing the Restricted Stock Legend are
transferred subsequently by such Holder, then, unless an applicable
registration statement has been declared effective under the Securities Act and
such shares are being transferred pursuant to such registration statement, the
Holder must deliver to the transfer agent for the Common Stock and to the
Company a certificate in substantially the form of Exhibit B as to
compliance with the restrictions on transfer applicable to such shares of
Common Stock and neither the transfer agent nor the registrar for the Common
Stock shall be required to register any transfer of such Common Stock not so
accompanied by a properly completed certificate.

Except in connection with an applicable registration
statement that has been declared effective under the Securities Act, if on or
prior to the Resale Restriction Termination Date certificates representing
shares of Common Stock are issued upon the registration of transfer, exchange
or replacement of any other certificate representing shares of Common Stock
bearing the Restricted Stock Legend, or if a request is made to remove such
Restricted Stock Legend from certificates representing shares of Common Stock,
the certificates so issued shall bear the Restricted Stock Legend, or the
Restricted Stock Legend shall not be removed, as the case may be, unless there
is delivered to the Company such reasonably satisfactory evidence, which, in
the case of a transfer made pursuant to Rule 144 under the Securities Act, may
include a written opinion from legal counsel, as may be reasonably required by
the Company, that neither the legend nor the restrictions on transfer set forth
therein are required to ensure that transfers thereof comply with the
Securities Act and that such shares of Common Stock are securities that are not
“restricted” within the meaning of Rule 144 under the Securities Act.  Upon transfer in connection with an
applicable registration statement that has been declared effective under the
Securities Act or after the Resale Restriction Termination Date or upon provision
to the Company of such reasonably satisfactory evidence, the Company shall
cause the transfer agent for the Common Stock to countersign and deliver
certificates representing shares of Common Stock that do not bear the
Restricted Stock Legend.

Section 2.16.   Additional Securities.

(a) The
Company may, from time to time, subject to compliance with any other applicable
provisions of this Indenture, without the consent of any Holder, create and
issue pursuant to this Indenture additional notes (“Additional  Securities”)
that shall have terms and conditions and “CUSIP” numbers identical to those of
the other outstanding Securities, except with respect to:

 23
 

 

(i)  the issue
date;

(ii)  the amount
of interest payable on the first Interest Payment Date therefor;

(iii)  the issue
price;

(iv)  any
adjustments necessary in order to conform to and ensure compliance with the
Securities Act (or other applicable securities laws) and any registration
rights or similar agreement applicable to such Additional Securities, which are
not adverse in any material respect to the Holder of any outstanding Securities
(other than such Additional Securities); and

(v) any Liquidated Damages payable as provided in
Section 7.05.

Any additional Securities and the Securities issued on
the Initial Issue Date, shall be treated as a single class for all purposes and
any such additional Securities will vote on all matters as one class with the
Securities issued on the Initial Issue Date. 
For purposes of this Indenture, references to the Securities include
Additional Securities, if any.

(b) With respect
to any Additional Securities, the Company will set forth in an Officers’
Certificate pursuant to a resolution of the Board of Directors of the Company,
copies of which will be delivered to the Trustee, the following information:

(i)  the
aggregate principal amount of such Additional Securities to be authenticated
and delivered pursuant to this Indenture;

(ii)  the issue
date and the issue price of such Additional Securities; provided that no Additional Securities may
be issued at a price that would cause such Additional Securities to have “original
issue discount” within the meaning of Section 1273 of the Internal Revenue Code
of 1986, as amended; and

(iii)  whether
such Additional Securities will be subject to transfer restrictions under the
Securities Act (or other applicable securities laws).

In addition, the Company will deliver to the Trustee
an Opinion of Counsel in accordance with Section 13.04 hereof certifying as to
the satisfaction of all conditions precedent to the authentication by the
Trustee of such Additional Securities.

Section 2.17.   Liquidated
Damages.

Under certain
circumstances, the Company may be obligated to pay Liquidated Damages to
Holders, as and to the extent set forth in any Registration Rights Agreement
and in accordance with Section 9.01 hereof. 
The terms of any such Registration Rights Agreement are hereby
incorporated herein by reference and any Liquidated Damages are deemed to be
interest for purposes of this Indenture. 
The Trustee has no duty to determine when Liquidated Damages
under any Registration Rights Agreement or Section 9.01 hereof should be paid.

 24

 

ARTICLE 3     PURCHASES OF SECURITIES UPON FUNDAMENTAL
CHANGE

Section 3.01.   Purchase of Securities at Option of
the Holder Upon Fundamental Change.

(a)  If at any
time that Securities remain outstanding there shall occur a Fundamental Change,
Securities shall be purchased by the Company at the option of the Holders, as
of the date that is 30 Business Days after the occurrence of the Fundamental
Change (the “Fundamental Change Purchase Date”) at a purchase price equal
to 100% of the principal amount of the Securities, together with any accrued
and unpaid interest to, but excluding, the Fundamental Change Purchase Date
(the “Fundamental Change Purchase Price”), payable in Cash, subject
to satisfaction by or on behalf of any Holder of the requirements set forth in
subsection (c) of this Section 3.01.  Notwithstanding the
foregoing, the Company may not repurchase the Securities upon the occurrence of
a Fundamental Change if the principal amount of the Securities has been
accelerated and such acceleration has not been rescinded on or prior to the
Fundamental Change Purchase Date.

A “Fundamental Change” shall
mean the occurrence of a Change in Control or a Termination of Trading.

A “Change in Control” shall
be deemed to have occurred if any of the following occurs after the date
hereof:

(i) any “person” or “group” (as such terms are defined
below) is or becomes the “beneficial owner” (as defined below), directly
or indirectly, of shares of Voting Stock of the Company representing 50% or
more of the total voting power of all outstanding classes of Voting Stock of
the Company or has the power, directly or indirectly, to elect a majority of
the members of the Board of Directors; or

(ii) the Company consolidates with, or merges with or
into, another Person or the Company sells, assigns, conveys, transfers, leases
or otherwise disposes of all or substantially all of the assets of the Company,
or any Person consolidates with, or merges with or into, the Company, in any
such event other than pursuant to a transaction in which the Persons that “beneficially
owned” (as defined below), directly or indirectly, shares of Voting Stock of
the Company immediately prior to such transaction “beneficially own” (as
defined below), directly or indirectly, shares of Voting Stock of the Company
representing at least a majority of the total voting power of all outstanding
classes of Voting Stock of the surviving or transferee Person; or

(iii) a majority of the members of the Board of
Directors are not Continuing Directors; or

(iv) the holders of the capital stock of the Company
approve any plan or proposal for the liquidation or dissolution of the Company
(whether or not otherwise in compliance with the terms hereof).

 25
 

 

For the purpose of the definition of “Change in Control”, (i) ”person”
and “group” have the meanings given such terms under
Section 13(d) and 14(d) of the Exchange Act or any successor
provision to either of the foregoing, and the term “group” includes any group
acting for the purpose of acquiring, holding or disposing of securities within
the meaning of Rule 13d-5(b)(1) under the Exchange Act (or any
successor provision thereto), (ii) a “beneficial owner” shall be
determined in accordance with Rule 13d-3 under the Exchange Act, as in
effect on the date of this Indenture, except that the number of shares of
Voting Stock of the Company shall be deemed to include, in addition to all
outstanding shares of Voting Stock of the Company and Unissued Shares deemed to
be held by the “person” or “group” (as such terms are defined above) or other
Person with respect to which the Change in Control determination is being made,
all Unissued Shares deemed to be held by all other Persons, and (iii) the
terms “beneficially owned” and “beneficially own” shall have meanings
correlative to that of “beneficial owner”.  The term “Unissued Shares” means
shares of Voting Stock not outstanding that are subject to options, warrants,
rights to purchase or conversion privileges exercisable within 60 days of the
date of determination of a Change in Control.

Notwithstanding anything to the contrary set forth in
this Section 3.01, Holders will not have the right to require the Company
to repurchase any Securities under clause (i) or clause (ii) of the definition
of “Change in Control” above, and the Company will not be required to deliver a
written notice of a Fundamental Change, if at least 90% of the consideration
paid for the Common Stock, excluding Cash payments for fractional shares and
Cash payments made pursuant to dissenters’ appraisal rights, in a merger, consolidation,
conveyance, sale, transfer or lease otherwise constituting a Change in Control
consists of shares of common stock traded on NASDAQ or another U.S. national or
regional securities exchange, or will be so traded immediately following the
merger or consolidation, and, as a result of the merger or consolidation, the
Securities become convertible into such shares of such common stock.

A “Termination of Trading” means
that the Common Stock or other securities into which the Securities are
convertible are not approved for listing on NASDAQ and are not listed for
trading on another U.S. national or regional securities exchange.

(b) Within 10 Business Days after the occurrence of a
Fundamental Change, the Company shall mail a written notice of the Fundamental
Change to the Trustee and to each Holder (and to beneficial owners as required
by applicable law).  The notice shall include the form of a Fundamental
Change Purchase Notice to be completed by the Holder and shall state:

(i)  the date of
such Fundamental Change and, briefly, the events causing such Fundamental
Change;

(ii) the date by which the Fundamental Change Purchase
Notice pursuant to this Section 3.01 must be given;

(iii)  the
Fundamental Change Purchase Date;

(iv)  the
Fundamental Change Purchase Price (including the amount of additional shares of
Common Stock that are deliverable, if any);

 26
 

 

(v) the Holder’s right to require the Company to
purchase the Securities;

(vi)  briefly,
the conversion rights of the Securities;

(vii)  the name
and address of each Paying Agent and Conversion Agent;

(viii)  the
Conversion Price and any adjustments thereto;

(ix)  that
Securities as to which a Fundamental Change Purchase Notice has been given may
be converted into Cash and Common Stock (if any) pursuant to Article 5 of
this Indenture only to the extent that the Fundamental Change Purchase Notice
has been withdrawn in accordance with the terms of this Indenture;

(x)  the
procedures that the Holder must follow to exercise rights under this
Section 3.01;

(xi)  the
procedures for withdrawing a Fundamental Change Purchase Notice, including a
form of notice of withdrawal; and

(xii)  that the
Holder must satisfy the requirements set forth in the Indenture and the
Securities in order to convert the Securities.

If any of the Securities is in the form of a Global
Security, then the Company shall modify such notice to the extent necessary to
accord with the procedures of the Depositary applicable to the repurchase of
Global Securities.

(c)  A Holder may
exercise its rights specified in subsection (a) of this
Section 3.01 upon delivery of a written notice (which shall be in
substantially the form included in Exhibit A hereto and which may
be delivered by letter, overnight courier, hand delivery, facsimile
transmission or in any other manner reasonably acceptable to the Paying Agent
and, in the case of Global Securities, may be delivered electronically or by
other means in accordance with the Depositary’s customary procedures) of the
exercise of such rights (a “Fundamental Change Purchase Notice”) to any
Paying Agent at any time prior to the close of business on the second Trading
Day next preceding the Fundamental Change Purchase Date.

The delivery of such Security to any Paying Agent
(together with all necessary endorsements) at the office of such Paying Agent
shall be a condition to the receipt by the Holder of the Fundamental Change
Purchase Price therefor.

The Company shall purchase from the Holder thereof,
pursuant to this Section 3.01, a portion of a Security if the principal
amount of such portion is $1,000 or an integral multiple of $1,000. 
Provisions of the Indenture that apply to the purchase of all of a Security
pursuant to Section 3.01 through Section 3.04 also apply to the
purchase of such portion of such Security.

Notwithstanding anything herein to the contrary, any
Holder delivering to a Paying Agent the Fundamental Change Purchase Notice
contemplated by this subsection (c) shall have the right to withdraw
such Fundamental Change Purchase Notice in whole or in a portion thereof that
is a principal amount of $1,000 or in an integral multiple thereof at any time
prior to 

 27
 

 

5:00 p.m., New York City time, on the second
Trading Day next preceding the Fundamental Change Purchase Date by delivery of
a written notice of withdrawal to the Paying Agent in accordance with
Section 3.02.

A Paying Agent shall promptly notify the Company of
the receipt by it of any Fundamental Change Purchase Notice or written
withdrawal thereof.

Anything herein to the contrary notwithstanding, in
the case of Global Securities, any Fundamental Change Purchase Notice may be
delivered or withdrawn and such Securities may be surrendered or delivered for
purchase in accordance with the Applicable Procedures as in effect from time to
time.

Section 3.02.   Effect of Fundamental Change
Purchase Notice.

Upon receipt by any Paying Agent of the Fundamental
Change Purchase Notice specified in Section 3.01(c), the Holder of the
Security in respect of which such Fundamental Change Purchase Notice was given
shall (unless such Fundamental Change Purchase Notice is withdrawn as specified
below) thereafter be entitled to receive the Fundamental Change Purchase Price
with respect to such Security.  Such Fundamental Change Purchase Price
shall be paid to such Holder promptly following the later of (a) the
Fundamental Change Purchase Date with respect to such Security (provided the conditions in
Section 3.01(c) have been satisfied) and (b) the time of
delivery of such Security to a Paying Agent by the Holder thereof in the manner
required by Section 3.01(c).  Securities in respect of which a
Fundamental Change Purchase Notice has been given by the Holder thereof may not
be converted into shares of Common Stock pursuant to Article 5 on or after
the date of the delivery of such Fundamental Change Purchase Notice unless such
Fundamental Change Purchase Notice has first been validly withdrawn.

A Fundamental Change Purchase Notice may be withdrawn
by means of a written notice (which may be delivered by mail, overnight
courier, hand delivery, facsimile transmission or in any other manner
reasonably acceptable to the Paying Agent and, in the case of Global
Securities, may be delivered electronically or by other means in accordance
with the Depositary’s customary procedures) of withdrawal delivered by the
Holder to a Paying Agent at any time prior to 5:00 p.m., New York City
time, on the second Trading Day immediately preceding the Fundamental Change
Purchase Date, specifying the principal amount of the Security or portion thereof
(which must be a principal amount of $1,000 or an integral multiple of $1,000
in excess thereof) with respect to which such notice of withdrawal is being
submitted.

Section 3.03.   Deposit of Fundamental Change
Purchase Price.

On or before 11:00 a.m., New York City time, on
the Fundamental Change Purchase Date, the Company shall deposit with the
Trustee or with a Paying Agent (other than the Company or an Affiliate of the
Company) an amount of money (in immediately available funds if deposited on
such Fundamental Change Purchase Date) sufficient to pay the aggregate
Fundamental Change Purchase Price of all the Securities or portions thereof
that are to be purchased as of such Fundamental Change Purchase Date.  The
manner in which the deposit required by this Section 3.03 is made by the
Company shall be at the option of the Company; provided
that such deposit shall be made in a manner reasonably acceptable to the
Trustee and 

 28
 

 

the Paying Agent such that the Trustee or a Paying
Agent shall have immediately available funds on the Fundamental Change Purchase
Date.

If a Paying Agent holds, in accordance with the terms
hereof, money sufficient to pay the Fundamental Change Purchase Price of any
Security for which a Fundamental Change Purchase Notice has been tendered and
not withdrawn in accordance with this Indenture, then, on the Fundamental
Change Purchase Date, such Security will cease to be outstanding and the rights
of the Holder in respect thereof shall terminate (other than the right to
receive the Fundamental Change Purchase Price as aforesaid).  The Company
shall publicly announce the principal amount of Securities purchased as a
result of such Fundamental Change on or as soon as practicable after the
Fundamental Change Purchase Date.

To the extent that the aggregate amount of Cash
deposited by the Company pursuant to this Section 3.03 exceeds the
aggregate Fundamental Change Purchase Price of the Securities or portions
thereof that the Company is obligated to purchase, then promptly after the
Fundamental Change Purchase Date the Trustee or a Paying Agent, as the case may
be, shall return any such excess Cash to the Company.

Section 3.04.   Securities Purchased in Part.

Any Security that is to be purchased only in part
shall be surrendered at the office of a Paying Agent, and promptly after the
Fundamental Change Purchase Date the Company shall execute and the Trustee
shall authenticate and deliver to the Holder of such Security, without service
charge, a new Security or Securities, of such authorized denomination or
denominations as may be requested by such Holder, in aggregate principal amount
equal to, and in exchange for, the portion of the principal amount of the
Security so surrendered that is not purchased.

Section 3.05.   Compliance with Securities Laws Upon
Purchase of Securities.

In connection with any offer to purchase or repurchase
Securities under Section 3.01, the Company shall (a) comply with
Rule 13e-4, Rule 14e-1 and any other tender offer rules under
the Exchange Act, (b) file the related Schedule TO (or any successor
or similar schedule, form or report), if required, under the Exchange Act and
(c) otherwise comply with all federal and state securities laws in
connection with such offer to purchase or repurchase Securities, all so as to
permit the rights of the Holders and obligations of the Company under
Section 3.01 through Section 3.04 to be exercised in the time and in
the manner specified therein.

Section 3.06.   No Fundamental Change Repurchase
Following Acceleration.

No Securities will be repurchased by the Company under
Section 3.01 if the principal amount of the Securities has been accelerated
under Section 9.02, and such acceleration has not been rescinded, on or prior
to the Fundamental Change Purchase Date.

Section 3.07.   Trustee’s Fundamental Change
Purchase Disclaimer.

The Trustee has no duty to determine when a
Fundamental Change has occurred, or when purchases of Securities upon a
Fundamental Change under Article 3 should be made.  The 

 29
 

 

Trustee shall not be accountable for and makes no
representation as to the Fundamental Change Purchase Price payable in respect
of any Fundamental Change.  The Trustee
shall not be responsible for the Company’s failure to comply with this Article
3.

ARTICLE 4     PAYMENT OF INTEREST AND ADDITIONAL SHARES

Section 4.01.   Interest Payments.

(a)  The Company
shall pay interest on the Securities at a rate of 0.50% per annum, payable
semi-annually in arrears on April 15 and October 15 of each year (each, an “Interest Payment Date”), or if any such day is not a Business Day, the
immediately following Business Day, commencing April 15, 2007.  Interest on a Security shall be paid to the
Holder of such Security at the close of business on April 1 or October 1 (each,
a “Record Date”), as the case may be, next
preceding the related Interest Payment Date, and shall be computed on the basis
of a 360-day year comprised of twelve 30-day months.  In the event of the
maturity, conversion, or purchase of a Security by the Company at the option of
the Holder, interest shall cease to accrue on such Security.

(b) Upon conversion of a Security, (i) a Holder
shall not receive any Cash payment of interest (unless such conversion occurs
between a Record Date and the Interest Payment Date to which it relates, in
which case a Holder on the Record Date will receive on the Interest Payment
Date accrued and unpaid interest) and the Conversion Rate shall not
be adjusted to account for accrued and unpaid interest and (ii) except as
set forth in clause (c) below, the Company’s delivery to a Holder of Cash
and shares, if any, of Common Stock into which the Security is convertible
shall be deemed to satisfy its obligation with respect to such Security, and
any accrued but unpaid interest shall be deemed to be paid in full upon
conversion, rather than cancelled, extinguished or forfeited.

(c)  Securities
surrendered for conversion by a Holder after the close of business on any
Record Date but prior to the next Interest Payment Date must be accompanied by
payment of an amount equal to the interest that the Holder is to receive on
the Securities; provided, however, that no such payment need be made
(1) if the Company has specified a Fundamental Change Purchase Date that
is after a Record Date and on or prior to the next Interest Payment Date,
(2) with respect to any Securities surrendered for conversion following
the Record Date for the payment of interest immediately preceding the Final
Maturity Date or (3) only to the extent of overdue interest, if any
overdue interest exists at the time of conversion with respect to such
Securities.

Section 4.02.   Additional Shares.

(a)  If a Holder
elects to convert its Securities pursuant to Section 5.01(b)(iii) hereof in
connection with a Qualifying Change in Control that occurs prior to the Final
Maturity Date, the Conversion Rate of the Securities being converted by such
Holder at that time shall be increased by an additional number of shares of
Common Stock (the “Additional Shares”)
determined by reference to the table attached as Schedule 4.02 hereto.  For avoidance of doubt, the adjustment
provided for in this Section 4.02 shall be made only with respect to the
Securities 

 30
 

 

converted in connection with such Qualifying Change in
Control and shall not be effective as to any Securities not so converted.

(b)  For purposes
of determining the applicable number of Additional Shares pursuant to Schedule
4.02:

(i)  “Effective Date” shall mean the date the
Qualifying Change in Control occurs or becomes effective; and

(ii)  “Stock Price” shall mean:

(x) in the case of a Qualifying Change in Control
described in clause (ii) of the definition of Change in Control, the price paid
per share of Common Stock in the Change in Control, unless the holders of
Common Stock receive only Cash in such Qualifying Change in Control, in which
event “Stock Price” shall mean the Cash amount paid per share;

(y) in the case of a Qualifying Change in Control
described in clause (i) of the definition of Change in Control, the average of
the last reported Closing Sale Prices of Common Stock over the five consecutive
Trading Day period ending on the Trading Day preceding the Effective Date of
such Qualifying Change in Control.

(c) If the Stock Price is between two Stock Price
amounts in the table attached as Schedule 4.02 hereto, the number of Additional
Shares shall be determined by a straight-line interpolation between the number
of Additional Shares set forth for the higher and lower Stock Price amounts,
based on a 365-day year.

(d) If the Effective Date falls between two Effective
Dates in the table attached as Schedule 4.02 hereto, the number of Additional
Shares shall be determined by a straight-line interpolation between the number
of Additional Shares set forth for the two dates, based on a 365-day year.

(e)  No increase
in the Conversion Rate shall be made pursuant to this Section 4.02 if the Stock
Price (i) exceeds $250.00 per share (subject to adjustment) or (ii) is less
than $62.17 per share (subject to adjustment).

(f)  The Stock
Price figures set forth in the first row of the table (i.e., column headers) in
Schedule 4.02 hereto shall be adjusted as of any date on which the Conversion
Price of the Securities is adjusted pursuant to Section 5.06.  The adjusted Stock Price figures shall equal
the Stock Price figures applicable immediately prior to such adjustment,
multiplied by a fraction, the numerator of which is the Conversion Price
immediately prior to the adjustment giving rise to the Stock Price figure
adjustment and the denominator of which is the Conversion Price as so adjusted.  The number of Additional Shares indicated in
the table shall be adjusted in the same manner as the Conversion Rate is
adjusted as a result of adjustments to the Conversion Price pursuant to Section
5.06.

 31
 

 

(g) In no event shall the Conversion Rate be increased
by more than 2.79 shares per $1,000 principal amount of Securities (the “Maximum Conversion Rate Adjustment”)
pursuant to the events described in this Section 4.02.  The Maximum Conversion Rate Adjustment shall
be subject to adjustments in the same manner as the Conversion Rate is adjusted
as a result of adjustments to the Conversion Price pursuant to Section 5.06.

(h) The Company will notify Holders of the anticipated
Effective Date of a Qualifying Change in Control and issue a press release as
soon as practicable after the Company first determines the anticipated
Effective Date of such Qualifying Change in Control.

ARTICLE 5     CONVERSION

Section 5.01.   Conversion Privilege.

(a)  Subject to
the further provisions of this Article 5 and paragraph 6 of the
Securities, a Holder of a Security may convert the principal amount of such
Security (or any portion thereof equal to $1,000 or any integral multiple of
$1,000 in excess thereof) into Cash and Common Stock at any time prior to the
close of business on July 15, 2011, at the Conversion Price then in effect, if,
during any calendar quarter (the “Quarter”)
(and only during such Quarter) commencing after the date hereof, the Closing
Sale Price of the Common Stock for at least 20 Trading Days in the period of 30
consecutive Trading Days ending on the last Trading Day of the Quarter
preceding the Quarter in which the conversion occurs is more than 120% of the
Conversion Price of the Securities in effect on that last Trading Day (the “Closing Sale Price Condition”), subject to the exceptions
provided in Section 5.01(b); provided, however, that
if such Security is submitted for purchase pursuant to Article 3, such
conversion right shall terminate at the close of business on the second Trading
Day immediately preceding the Fundamental Change Purchase Date for such
Security or such earlier date as the Holder presents such Security for purchase
pursuant to Article 3 (unless the Company shall default in making the
Fundamental Change Purchase Price payment when due, in which case the conversion
right shall terminate at the close of business on the date such default is
cured and such Security is purchased).

Provisions of this Indenture that apply to conversion
of all of a Security also apply to conversion of a portion of a Security.

A Security in respect of which a Holder has delivered
a Fundamental Change Purchase Notice pursuant to
Section 3.01(c) exercising the option of such Holder to require the
Company to purchase such Security may be converted only if such Fundamental
Change Purchase Notice is withdrawn by a written notice of withdrawal delivered
to a Paying Agent prior to 5:00 p.m., New York City time, on the second
Trading Day immediately preceding the Fundamental Change Purchase Date in
accordance with Section 3.02.

A Holder of Securities is not entitled to any rights
of a holder of Common Stock until such Holder has converted its Securities to
Common Stock and only to the extent such Securities are deemed to have been
converted into Common Stock pursuant to this Article 5.

(b) Even if the Closing Sale Price Condition is not
satisfied,

 32
 

 

(i)  if the
Trading Price for the Securities on each Trading Day during any five
consecutive Trading Day period was less than 95% of the Closing Sale Price of
Common Stock on such date multiplied by the then current Conversion Rate, a
Holder may surrender Securities for conversion at any time during the following
10 Trading Days;

For the avoidance of doubt, the five dates of
determination within any five consecutive Trading Day period referred to above
shall not include (i) any day on which there is a Market Disruption Event or
(ii) any day on which NASDAQ or, if the Common Stock is not listed on NASDAQ,
the principal other U.S. national or regional securities exchange on which the
Common Stock is then listed is not open for trading.

(ii)  in the
event that the Company declares

(A)  a dividend or distribution of any
rights or warrants to all holders of Common Stock entitling them to subscribe
for or purchase shares of Common Stock at a price per share less than the
Current Market Price per share (as defined in Section 5.06(e)) on the
record date for such dividend or distribution, or

(B)  a dividend or distribution of Cash,
debt securities (or other evidences of Indebtedness) or other assets (excluding
dividends or distributions for which a Conversion Price adjustment is required
to be made under Section 5.06(a) or 5.06(b) of this Indenture)
where the fair market value of such dividend or distribution per share of
Common Stock, as determined in this Indenture, together with all other such
dividends and distributions within the preceding twelve months, exceeds 15% of
the Current Market Price of the Common Stock as of the Trading Day immediately
prior to the date of declaration for such dividend or distribution,

then the Securities may be surrendered for conversion
beginning on the date the Company gives notice to the Holders of such right,
which shall not be less than 20 days prior to the ex-dividend time for such
dividend or distribution, until the earlier of the close of business on the
Business Day prior to the ex-dividend time or until the Company announces that
such distribution will not take place;

(iii)  upon the
occurrence of a Fundamental Change with respect to the Company, the Securities
may be surrendered for conversion at any time from or after the date which is
40 days prior to the anticipated effective time of the Fundamental Change as
announced by the Company, which announcement must occur, to the extent
practicable, not earlier than 70 days nor later than 40 days prior to such
anticipated effective time, until the close of business on the second Trading
Day immediately preceding the Fundamental Change Purchase Date;

(iv)  if the
Company consolidates with or merges with or into another Person or is a party
to a binding share exchange or conveys, transfers, sells, leases or otherwise
disposes of all or substantially all of its properties and assets in each case
pursuant to which the Common Stock would be converted into Cash, securities
and/or other property, the Securities may be surrendered for conversion at any
time from or after the date which 

 33
 

 

is 15 days prior to the date announced by the Company
as the anticipated effective date of the transaction and until and including
the date that is 15 days after the date that is the effective date of such
transaction; provided such
transaction does not otherwise constitute a Fundamental Change (to which the
provisions of Sections 5.01(b)(iii) and 5.01(c) shall instead apply) (any such
transaction to which this Section 5.01(b)(iv) applies, a “Transforming Transaction”); the Company
shall notify Holders of Securities at least 20 days prior to the anticipated
effective date of such Transforming Transaction and the Board of Directors
shall determine the anticipated effective date of such Transforming
Transaction, and such determination shall be conclusive and binding on the
Holders and shall be publicly announced by the Company and posted on its web
site not later than two Business Days prior to such 15th day; and

(v) at any time after July 15, 2011 and prior to the
close of business on the Business Day immediately preceding the Final Maturity
Date, the Securities may be surrendered for conversion regardless of whether
any of the foregoing conditions has been satisfied.

(c) Pursuant to Section 5.01(b)(iii), if a Holder
converts Securities at any time from or after the date which is 40 days prior
to the anticipated effective time of any Fundamental Change as announced by the
Company until the close of business on the second Trading Day immediately
preceding the Fundamental Change Purchase Date, such Holder shall receive:

(i)  if such
Securities are surrendered for conversion at any time beginning 25 Trading
Days before the date of payment of consideration in connection with a Change in
Control, Cash and, with respect to the Daily Net Share Settlement Value (if
any), the kind of securities and other assets or property received by holders
of the Common Stock in such Change in Control; or

(ii)  in all
other events, Cash or a combination of Cash and Common Stock, in the same
manner as described in Section 5.05;

in each case, taking into account any Additional
Shares deliverable as a result of any Qualifying Change in Control pursuant to
Section 4.02.

(d) Upon request, the Conversion Agent, on behalf of
the Company, will determine whether the Securities are convertible pursuant to the first
paragraph of Section 5.01(a) and clause (i) of Section 5.01(b), and, if
so, will notify the Trustee and the Company in writing.

(e) The Conversion Agent shall have no obligation to
determine the Trading Price of the Securities unless the Company has requested
such determination in writing, and the Company shall have no
obligation to make such request unless the Trustee, acting at the request of
one or more Holders holding, in the aggregate, at least $5,000,000 in principal
amount of Securities, provides the Company with reasonable evidence that the
Trading Price of the Securities on any Trading Day would be less than 95% of
the product
of the then current Conversion Rate multiplied by the Closing Sale Price of the
Common Stock on that date.  At
such time, the Company shall instruct the Conversion Agent to determine the
Trading Price of 

 34

 

the Securities beginning on such Trading Day and on
each successive Trading Day for four consecutive Trading Days.

Section 5.02.   Conversion Procedure.

The right to convert any Security may be exercised, if
such Security is represented by a Global Security, by book-entry transfer to
the Conversion Agent (which initially shall be the Trustee) through the
facilities of the Depositary in accordance with the Applicable Procedures or,
if such Security is represented by a Certificated Security, by delivery of such
Security at the specified office of the Conversion Agent, accompanied, in
either case, by (a) a completed and duly signed conversion notice, in the
form as set forth on the reverse of Security attached hereto as Exhibit A
(a “Conversion Notice”); (b) if the Security
is represented by a Certificated Security and such Certificated Security has
been lost, stolen, destroyed or mutilated, a notice to the Conversion Agent in
accordance with Section 2.07 regarding the loss, theft, destruction or
mutilation of the Security; (c) appropriate endorsements and transfer
documents if required by the Conversion Agent; and (d) payment of any tax
or duty, in accordance with Section 5.04, which may be payable in respect
of any transfer involving the issue or delivery of the Common Stock in the name
of a Person other than the Holder of the Security.  The “Conversion Date” shall be
the Business Day on which the Holder satisfies all of the requirements set
forth in the immediately preceding sentence, if all such requirements shall
have been satisfied by 11:00 a.m., New York City time, on such day, and in
all other cases, the Conversion Date shall be the next succeeding Business Day;
however, if a Holder surrenders for conversion a Security at any time after the
25th scheduled Trading Day prior to the Final Maturity Date, the Conversion
Date shall be deemed to be the Business Day immediately preceding the Final
Maturity Date.  On the third Business Day
following the last day of the related Conversion Period, subject to
Section 5.05, the Company shall deliver to the Holder through a Conversion
Agent a certificate for the number of whole shares of Common Stock (or the
other form of consideration into which the Common Stock has been converted in
connection with a Transforming Transaction) issuable upon the conversion and
Cash (including Cash in lieu of any fractional shares pursuant to
Section 5.03).

The person in whose name the Common Stock certificate
is registered shall be deemed to be a stockholder of record on the Conversion
Date; provided, however, that no surrender of a
Security on any date when the stock transfer books of the Company shall be
closed shall be effective to constitute the person or persons entitled to
receive the shares of Common Stock upon such conversion as the record holder or
holders of such shares of Common Stock on such date, but such surrender shall
be effective to constitute the person or persons entitled to receive such
shares of Common Stock as the record holder or holders thereof for all purposes
at the close of business on the next succeeding day on which such stock
transfer books are open; provided, further, that
such conversion shall be at the Conversion Price in effect for the 20 Trading
Days beginning on the third Trading Day immediately following the Conversion
Date as if the stock transfer books of the Company had not been closed. 
Upon conversion of a Security, such person shall no longer be a Holder of such
Security.  No payment or adjustment will be made for dividends or
distributions on shares of Common Stock issued upon conversion of a Security.

Upon surrender of a Security that is converted in
part, the Company shall execute, and the Trustee, upon receipt of an Officers’
Certificate and Opinion of Counsel delivered in 

 35
 

 

accordance with Section 13.04 hereof shall
authenticate and deliver to the Holder, a new Security equal in principal
amount to the unconverted portion of the Security surrendered.

Section 5.03.   Fractional Shares.

The Company will not issue fractional shares of Common
Stock upon conversion of Securities.  In lieu thereof, the Company will
deliver a number of shares of Common Stock equal to the aggregate of the
fractional shares otherwise deliverable for each Trading Day during the
Conversion Period (rounding down to the nearest whole number) and Cash equal to
the remainder multiplied by the Volume Weighted Average Price of the Common
Stock on the last day of the Conversion Period.

Section 5.04.   Taxes on Conversion.

If a Holder converts a Security, the Company shall pay
any documentary, stamp or similar issue or transfer tax due on the issue of
shares of Common Stock upon such conversion.  However, the Holder shall
pay any such tax which is due because the Holder requests the shares to be
issued in a name other than the Holder’s name.  The Conversion Agent may
refuse to deliver the certificate representing the Common Stock being issued in
a name other than the Holder’s name until the Conversion Agent receives a sum
sufficient to pay any tax which will be due because the shares are to be issued
in a name other than the Holder’s name.  Nothing herein shall preclude any
tax withholding required by law or regulation.

Section 5.05.   Payment Upon Conversion.

(a) Except as otherwise provided in Section
5.01(c)(i), in the event that the Company receives a Holder’s valid Conversion
Notice:

(i) For each $1,000 aggregate principal amount of
Securities surrendered for conversion, the Company shall be required to pay to
such Holder the aggregate of the following (the “Conversion Obligation”)
for each of the twenty Trading Days beginning on the third Trading Day
following the Conversion Date (such twenty Trading Day period, a “Conversion Period”):

(A)  if the Daily Conversion
Value (as defined below) for such Trading Day for each $1,000 aggregate
principal amount of Securities exceeds $50.00, (1) a Cash payment of
$50.00 and (2) the remaining Daily Conversion Value (the “Daily Net Share Settlement Value”) in shares of Common Stock
(or the other form of consideration into which the Common Stock has been
converted in connection with a Transforming Transaction); or

(B) if the Daily Conversion Value for such Trading Day
for each $1,000 aggregate principal amount of Securities is less than or equal
to $50.00, a Cash payment equal to the Daily Conversion Value.

(C) Notwithstanding the foregoing, if a Holder
surrenders for conversion a Security at any time after the twenty-fifth
scheduled Trading Day 

 36
 

 

immediately preceding the
Final Maturity Date and on or prior to the close of business on the Business
Day immediately preceding the Final Maturity Date, (1) the Conversion Date
will be deemed to be the Business Day immediately preceding the Final Maturity
Date, (2) the Conversion Period for such conversion will be the twenty
Trading Day period commencing on the Trading Day immediately following the
Final Maturity Date, (3) in lieu of receiving any Cash payments as set
forth pursuant to clause (A) or (B) above, the Holder
will receive a Cash payment on the Final Maturity Date of $1,000 per
$1,000 aggregate principal amount of Securities surrendered and (4) on the
third Business Day following the last day of such Conversion Period, the Holder
will receive an amount of shares of Common Stock, if any, equal to the
aggregate of, for each Trading Day during the Conversion Period, any Daily
Conversion Value in excess of $50.00 pursuant to clause (ii) below.

(ii)  The amount
to be paid to a converting Holder shall be computed in accordance with the
following:

(A) The “Daily Conversion Value”
for each Trading Day during the Conversion Period for each $1,000 aggregate
principal amount of Securities is equal to one-twentieth of the product of the
then applicable Conversion Rate multiplied by the Volume Weighted Average Price
of the Common Stock (or such other form of consideration into which the Common
Stock has been converted in connection with a Fundamental Change) on such
Trading Day.

(B)  T he number of shares of Common Stock to
be delivered under Section 5.05(a)(i)(A)(2) or
5.05(a)(i)(C)(4) shall be determined by dividing the Daily Net Share
Settlement Value by the Volume Weighted Average Price of the Common Stock (or
such other form of consideration into which the Common Stock has been converted
in connection with a Fundamental Change) for such Trading Day.

(C)  For purposes of this Section 5.05,
“Volume Weighted Average Price” per
share of Common Stock (or any security into which the Common Stock has been
converted in connection with a Fundamental Change) on any Trading Day means the
volume weighted average price on the principal exchange or over-the-counter
market on which the Common Stock (or such other security) is then listed or
traded, from 9:30 a.m. to 4:00 p.m. (New York City time) on that
Trading Day as displayed under the heading “Bloomberg VWAP” on Bloomberg
Page UTHR Equity AQR (or the Bloomberg Page for any security into
which the Common Stock has been converted in connection with a Fundamental
Change), or if such Volume Weighted Average Price is not available, the Board
of Directors’ reasonable, good faith estimate of the volume weighted average
price of the shares of Common Stock (or other security) on such Trading Day
(whose determination shall be conclusive evidence of such Volume Weighted
Average Price and which shall be evidenced by an Officers’ Certificate
delivered to the Trustee and the Conversion Agent).

 37
 

 

(b) The Company shall, prior to the issuance of any
Securities hereunder, and from time to time as may be necessary, reserve at all
times and keep available, free from preemptive rights, out of its authorized
but unissued Common Stock, a sufficient number of shares of Common Stock
deliverable upon conversion of all of the Securities.

(c) All shares of Common Stock that may be issued upon
conversion of the Securities shall be duly authorized, validly issued, fully
paid and nonassessable and shall be free of any preemptive rights and free of
any lien or adverse claim.

(d) The Company shall endeavor to comply with all
applicable securities laws regulating the offer and delivery of any Common
Stock upon conversion of Securities and shall list or cause to have quoted such
shares of Common Stock on each national or regional securities exchange or
other over-the-counter market or such other market on which the Common Stock is
then listed or quoted; provided, however, that, if the rules of such
automated quotation system or exchange permit the Company to defer the listing
of such Common Stock until the first conversion of the Securities into Common
Stock in accordance with the provisions of this Indenture, the Company
covenants to list such Common Stock issuable upon conversion of the Securities
in accordance with the requirements of such automated quotation system or
exchange at such time. Any Common Stock issued upon conversion of a Security
hereunder which at the time of conversion was a Transfer Restricted Security
shall also be a Transfer Restricted Security.

(e) Notwithstanding anything herein to the contrary,
nothing herein shall give to any Holder any rights as a creditor in respect of
its right to conversion.

Section 5.06.   Adjustment of Conversion Price.

The conversion price as stated in paragraph 6 of the
Securities (the “Conversion Price”) shall be adjusted from
time to time by the Company as follows:

(a) In case the Company shall (i) pay a dividend
on its Common Stock in shares of Common Stock, (ii) make a distribution on
its Common Stock in shares of Common Stock, (iii) subdivide its
outstanding Common Stock into a greater number of shares, or (iv) combine
its outstanding Common Stock into a smaller number of shares, the Conversion
Price in effect immediately prior thereto shall be adjusted so that the Holder
of any Security thereafter surrendered for conversion shall be entitled to
receive that number of shares of Common Stock which it would have owned had
such Security been converted immediately prior to the record date of such event
or the happening of such event (assuming such Security were convertible solely
into shares of Common Stock, based on the relevant Conversion Price, rather
than Cash or Cash and Common Stock as set forth in Section 5.05).  An
adjustment made pursuant to this subsection (a) shall become
effective immediately after the record date in the case of a dividend or
distribution and shall become effective immediately after the effective date in
the case of subdivision or combination.

(b) In case the Company shall issue rights or warrants
to all or substantially all holders of its Common Stock entitling them for a
period of not more than 60 days to subscribe for or purchase shares of Common
Stock (or securities convertible into Common Stock) at a 

 38
 

 

price per share (or having a conversion price per
share) less than the Current Market Price per share of Common Stock (as
determined in accordance with subsection (e) of this
Section 5.06) on the record date for the determination of stockholders
entitled to receive such rights or warrants, the Conversion Price in effect
immediately prior thereto shall be adjusted so that the same shall equal the
price determined by multiplying the Conversion Price in effect immediately
prior to such record date by a fraction of which the numerator shall be the
number of shares of Common Stock outstanding on such record date plus the
number of shares which the aggregate offering price of the total number of
shares of Common Stock so offered (or the aggregate conversion price of the
convertible securities so offered, which shall be determined by multiplying the
number of shares of Common Stock issuable upon conversion of such convertible
securities by the conversion price per share of Common Stock pursuant to the
terms of such convertible securities) would purchase at the Current Market
Price per share (as defined in subsection (e) of this
Section 5.06) of Common Stock on such record date, and of which the
denominator shall be the number of shares of Common Stock outstanding on such
record date plus the number of additional shares of Common Stock offered (or
into which the convertible securities so offered are convertible).  Such
adjustment shall be made successively whenever any such rights or warrants are
issued and shall become effective immediately after such record date.  If
at the end of the period during which such rights or warrants are exercisable
not all rights or warrants shall have been exercised or distributed, the
adjusted Conversion Price shall be immediately readjusted to what it would have
been based upon the number of additional shares of Common Stock actually issued
(or the number of shares of Common Stock issuable upon conversion of
convertible securities actually issued).

(c) In case the Company shall distribute to all or
substantially all holders of its Common Stock any shares of capital stock of
the Company (other than Common Stock), evidences of Indebtedness or other
non-Cash assets (including securities of any person other than the Company but
excluding (1) dividends or distributions paid exclusively in Cash referred
to in subsection (d) of this Section 5.06 or (2) dividends or
distributions referred to in subsection (a) of this
Section 5.06), or shall distribute to all or substantially all holders of
its Common Stock rights or warrants to subscribe for or purchase any of its
securities (excluding those rights and warrants referred to in
subsection (b) of this Section 5.06 and also excluding the
distribution of rights to all holders of Common Stock pursuant to the adoption
of a stockholder rights plan or the detachment of such rights under the terms
of such stockholder rights plan), then in each such case the Conversion Price
shall be adjusted so that the same shall equal the price determined by
multiplying the current Conversion Price by a fraction of which the numerator
shall be the Current Market Price per share (as defined in
subsection (e) of this Section 5.06) of the Common Stock on the
record date mentioned below less the fair market value on such record date (as
determined by the Board of Directors, whose determination shall be conclusive evidence
of such fair market value and which shall be evidenced by an Officers’
Certificate delivered to the Trustee and the Conversion Agent) of the portion
of the capital stock, evidences of indebtedness or other non-Cash assets so
distributed or of such rights or warrants applicable to one share of Common
Stock (determined on the basis of the number of shares of Common Stock
outstanding on the record date), and of which the denominator shall be the
Current Market Price per share (as defined in subsection (e) of this
Section 5.06) of the Common Stock on such record date.  Such
adjustment shall be made successively whenever any such distribution is made
and 

 39
 

 

shall become effective immediately after the record
date for the determination of shareholders entitled to receive such
distribution.

In the event the then fair market value (as so
determined) of the portion of the capital stock, evidences of Indebtedness or
other non-Cash assets so distributed or of such rights or warrants applicable
to one share of Common Stock is equal to or greater than the Current Market
Price per share of the Common Stock on such record date, in lieu of the
foregoing adjustment, adequate provision shall be made so that each holder of a
Security shall have the right to receive upon conversion the amount of capital
stock, evidences of indebtedness or other non-Cash assets so distributed or of
such rights or warrants such holder would have received had such holder
converted each Security on such record date.  In the event that such dividend
or distribution is not so paid or made, the Conversion Price shall again be
adjusted to be the Conversion Price which would then be in effect if such
dividend or distribution had not been declared.  If the Board of Directors
determines the fair market value of any distribution for purposes of this
Section 5.06(c) by reference to the actual or when issued trading
market for any securities, it must in doing so consider the prices in such
market over the same period used in computing the Current Market Price of the
Common Stock.

In the event that the Company implements a preferred
shares rights plan (“Rights Plan”), upon
conversion of the Securities into Common Stock, to the extent that the Rights
Plan has been implemented and is still in effect upon such conversion, the
Holders of Securities will receive, in addition to the Common Stock, the rights
described therein (whether or not the rights have separated from the Common
Stock at the time of conversion), subject to the limitations set forth in the
Rights Plan.  Any distribution of rights or warrants pursuant to a Rights
Plan complying with the requirements set forth in the immediately preceding
sentence of this paragraph shall not constitute a distribution of rights or
warrants pursuant to this Section 5.06(c).

Rights or warrants distributed by the Company to all
holders of Common Stock entitling the holders thereof to subscribe for or
purchase shares of the Company’s Capital Stock (either initially or under
certain circumstances), which rights or warrants, until the occurrence of a
specified event or events (“Trigger Event”): 
(i) are deemed to be transferred with such shares of Common Stock;
(ii) are not exercisable; and (iii) are also issued in respect of
future issuances of Common Stock, shall be deemed not to have been distributed
for purposes of this Section 5.06 (and no adjustment to the Conversion
Price under this Section 5.06 will be required) until the occurrence of
the earliest Trigger Event, whereupon such rights and warrants shall be deemed
to have been distributed and an appropriate adjustment (if any is required) to
the Conversion Price shall be made under this Section 5.06(c).  If
any such right or warrant, including any such existing rights or warrants
distributed prior to the date of this Indenture, are subject to events, upon
the occurrence of which such rights or warrants become exercisable to purchase
different securities, evidences of indebtedness or other assets, then the date
of the occurrence of any and each such event shall be deemed to be the date of
distribution and record date with respect to new rights or warrants with such
rights (and a termination or expiration of the existing rights or warrants
without exercise by any of the holders thereof).  In addition, in the
event of any distribution (or deemed distribution) of rights or warrants, or
any Trigger Event or other event (of the type described in the preceding
sentence) with respect thereto that was counted for purposes of calculating a
distribution amount for which an adjustment to the Conversion Price under this
Section 5.06 was made, (1) in the case of any such rights or warrants
which shall all 

 40
 

 

have been redeemed or repurchased without exercise by
any holders thereof, the Conversion Price shall be readjusted upon such final
redemption or repurchase to give effect to such distribution or Trigger Event,
as the case may be, as though it were a Cash distribution, equal to the per
share redemption or repurchase price received by a holder or holders of Common
Stock with respect to such rights or warrants (assuming such holder had
retained such rights or warrants), made to all holders of Common Stock as of
the date of such redemption or repurchase, and (2) in the case of such
rights or warrants which shall have expired or been terminated without exercise
by any holders thereof, the Conversion Price shall be readjusted as if such
rights and warrants had not been issued.

(d)  (1) In case
the Company shall, by dividend or otherwise, at any time distribute (a “Triggering Distribution”) to all or substantially all holders of its
Common Stock Cash dividends and other Cash distributions (other than (x)
distributions described in Section 5.06(d)(2) below, (y) any dividend or
distribution in connection with liquidation, dissolution or winding up or (z)
any regular quarterly Cash dividend on Common Stock (subject to adjustment)),
the Conversion Price shall be reduced so that the same shall equal the price
determined by dividing such Conversion Price in effect on the record date with
respect to such Cash dividend or distribution by a fraction of which the
numerator shall be the Current Market Price per share of the Common Stock (as
determined in accordance with subsection (e) of this
Section 5.06) as of the day before the “ex” date with respect to the
dividend or distribution, and the denominator shall be such Current Market
Price per share of the Common Stock (as determined in accordance with
subsection (e) of this Section 5.06) as of the day before the “ex”
date with respect to the dividend or distribution less the Dividend Adjustment
Amount (as defined below), such decrease to become effective immediately prior
to the opening of business on the day following the date on which the
Triggering Distribution is paid; provided, however, that,
in the event the portion of the Triggering Distribution applicable to one share
of Common Stock is equal to or greater than the Current Market Price on such
record date, in lieu of the foregoing adjustment, adequate provision shall be
made so that each Holder shall have the right to receive upon conversion the
amount of Cash such Holder would have received had such Holder converted each
Security on such record date.  In the event that such dividend or
distribution is not so paid or made, the Conversion Rate shall again be
adjusted to be the Conversion Rate that would then be in effect if such
dividend or distribution had not been declared.

(2)  In case any tender offer
made by the Company or any of its Subsidiaries for Common Stock shall expire
and such tender offer (as amended upon the expiration thereof) shall involve
the payment of aggregate consideration in an amount (determined as the sum of
the aggregate amount of Cash consideration and the aggregate fair market value
(as determined by the Board of Directors, whose determination shall be
conclusive evidence thereof and which shall be evidenced by an Officers’
Certificate delivered to the Trustee and the Conversion Agent thereof) of any
other consideration) that exceeds an amount equal to the Current Market Price per
share of Common Stock (as determined in accordance with
subsection (e) of this Section 5.06) as of the last date (the “Expiration Date”) tenders could have been made pursuant to such tender
offer (as it may be amended) (the last time at which such tenders could have
been made 

 41
 

 

on the Expiration Date is
hereinafter sometimes called the “Expiration Time”), then,
immediately prior to the opening of business on the day after the Expiration
Date, the Conversion Price shall be reduced so that the same shall equal the
price determined by multiplying the Conversion Price in effect immediately
prior to the close of business on the Expiration Date by a fraction of which
the numerator shall be the product of the number of shares of Common Stock
outstanding (including tendered shares but excluding any shares held in the
treasury of the Company) at the Expiration Time multiplied by the Current
Market Price per share of the Common Stock (as determined in accordance with
subsection (e) of this Section 5.06) on the Trading Day next
succeeding the Expiration Date and the denominator shall be the sum of (x) the
aggregate consideration (determined as aforesaid) payable to stockholders based
on the acceptance (up to any maximum specified in the terms of the tender
offer) of all shares validly tendered and not withdrawn as of the Expiration
Time (the shares deemed so accepted, up to any such maximum, being referred to
as the “Purchased Shares”) and (y) the product of
the number of shares of Common Stock outstanding (less any Purchased Shares and
excluding any shares held in the treasury of the Company) at the Expiration
Time and the Current Market Price per share of Common Stock (as determined in
accordance with subsection (e) of this Section 5.06) on the
Trading Day next succeeding the Expiration Date, such reduction to become
effective immediately prior to the opening of business on the day following the
Expiration Date.  In the event that the Company is obligated to purchase
shares pursuant to any such tender offer, but the Company is permanently
prevented by applicable law from effecting any or all such purchases or any or
all such purchases are rescinded, the Conversion Price shall again be adjusted
to be the Conversion Price which would have been in effect based upon the number
of shares actually purchased.  If the application of this
Section 5.06(d)(2) to any tender offer would result in an increase in
the Conversion Price, no adjustment shall be made for such tender offer under
this Section 5.06(d)(2).

(3) For purposes of this Section 5.06(d), the
term “tender offer” shall mean and include both tender offers and exchange
offers, all references to “purchases” of shares in tender offers (and all
similar references) shall mean and include both the purchase of shares in
tender offers and the acquisition of shares pursuant to exchange offers, and
all references to “tendered shares” (and all similar references) shall mean and
include shares tendered in both tender offers and exchange offers.

(e) For the purpose of any computation under
subsections (b), (c)  and (d) of this Section 5.06,
(i) the current market price (the “Current Market Price”)
shall mean, with respect to any date of determination, the Closing Sale Price
per share of Common Stock on the date of determination.  For purposes
hereof, the term “ex” date, when used with respect to any dividend or
distribution, means the first date on which the Common Stock trades, regular
way, on the relevant exchange or in the relevant market from which the Closing
Sale Price was obtained without the right to receive such dividend or
distribution; (ii) “Dividend Adjustment
Amount” 

 42
 

 

means the full amount of the dividend or distribution
to the extent payable in Cash applicable to one common share.

(f)  In any case
in which this Section 5.06 shall require that an adjustment be made
following a record date or Expiration Date, as the case may be, established for
purposes of this Section 5.06, the Company may elect to defer (but only
until five Business Days following the filing by the Company with the Trustee
of the certificate described in Section 5.10) issuing to the Holder of any
Security converted after such record date or Expiration Date the shares of
Common Stock and other capital stock of the Company issuable upon such
conversion over and above the shares of Common Stock and other capital stock of
the Company issuable, or Cash payable, upon such conversion only on the basis
of the Conversion Price prior to adjustment; and, in lieu of the shares the
issuance of which, or Cash the payment of which, is so deferred, the Company
shall issue or cause its transfer agents to issue due bills or other
appropriate evidence prepared by the Company of the right to receive such
shares or Cash, as the case may be.  If any distribution in respect of
which an adjustment to the Conversion Price is required to be made as of the
record date or Expiration Date therefor is not thereafter made or paid by the
Company for any reason, the Conversion Price shall be readjusted to the
Conversion Price which would then be in effect if such record date had not been
fixed or such effective date or Expiration Date had not occurred.

Section 5.07.   No Adjustment.

Notwithstanding the provisions of Section 5.06, no
adjustment in the Conversion Rate shall be required unless the adjustment would
result in a change of at least 1% in the Conversion Price as last adjusted; provided, however, that any adjustments which by reason of this
Section 5.07 are not required to be made shall be carried forward and
taken into account in any subsequent adjustment, regardless of whether the
aggregate adjustment is less than 1% within one year of the first such adjustment
carried forward upon required purchases of the Securities in connection with a
Fundamental Change and five Business Days prior to the Final Maturity
Date.  All calculations under this Article 5 shall be made to the
nearest cent or to the nearest one-hundredth of a share, as the case may be.

Except as otherwise provided herein, no adjustment
need be made for issuances of Common Stock pursuant to a Company plan for
reinvestment of dividends or interest or for a change in the par value or a
change to no par value of the Common Stock.

To the extent that the Securities become convertible
into the right to receive Cash, no adjustment need be made thereafter as to the
Cash.  Interest will not accrue on the
Cash.

No adjustment to the Conversion Rate will be required
in respect of any transaction that Holders will participate in without
conversion of the Securities.

Section 5.08.   Adjustment for Tax Purposes.

The Company shall be entitled to make such reductions
in the Conversion Price, for the remaining term of the Securities or any
shorter term, in addition to those required by Section 5.06, as the Board
of Directors shall determine to be advisable in order to avoid or 

 43
 

 

diminish any tax to any
holders of shares of Common Stock or rights to purchase Common Stock resulting
from any stock dividends, subdivisions of shares, distributions of rights or
warrants to purchase or subscribe for stock or securities, distributions of
securities convertible into or exchangeable for stock hereafter made by the
Company to its stockholders or from any event treated as such for income tax
purposes.

Section 5.09.   Temporary Reduction of Conversion
Price.

To the extent permitted by applicable law, the Company
from time to time may reduce the Conversion Price by any amount for any period of
time if the period is at least 20 Business Days, the reduction is irrevocable
during such period, and the Board of Directors shall have made a determination
that such reduction would be in the best interest of the Company.  Whenever the Conversion Price is reduced
pursuant to the preceding sentence, the Company shall provide notice of any
reduction in the Conversion Price to the Holders in the manner provided in
Section 13.02, with a copy to the Trustee and Conversion Agent, at least 15
days prior to the date such reduced Conversion Price takes effect, and such
notice shall state the reduced Conversion Price and the period during which it
will be in effect.

Section 5.10.   Notice of Certain Transactions.

In the event that:

(1) the Company takes any action which would require
an adjustment in the Conversion Price;

(2) the Company consolidates or merges with, or
transfers all or substantially all of its property and assets to, another
corporation and shareholders of the Company must approve the transaction; or

(3) there is a dissolution or liquidation of the
Company,

the Company shall mail to Holders and file with the
Trustee a notice stating the proposed record or effective date, as the case may
be, and mail the notice at least 10 days before such date; provided, further, that upon occurrence of
an event referred to in clause (1) of this Section 5.10, the Company shall file
with the Trustee (and deliver a copy to the Conversion Agent) an Officers’
Certificate briefly stating the facts requiring the adjustment and the manner
of computing it and promptly mail to Holders a notice of the adjustment.  Failure to mail such notice or any defect
therein shall not affect the validity of any transaction referred to in clause
(1), (2) or (3) of this Section 5.10; provided, however, that unless and until the Trustee and the
Conversion Agent shall have received an Officers’ Certificate setting forth an
adjustment of the Conversion Price in connection with the event referred to in
clause (1), the Trustee may assume without inquiry that the Conversion Price
has not been adjusted and that the last Conversion Price of which it has
knowledge remains in effect.

 44

 

Section 5.11.   Effect of Reclassification,
Consolidation, Merger or Sale on Conversion Privilege.

If any of the following shall occur, namely: 
(a) any reclassification or change of shares of Common Stock issuable upon
conversion of the Securities (other than a change in par value, or from par
value to no par value, or from no par value to par value, or as a result of a
subdivision or combination, or any other change for which an adjustment is
provided in Section 5.06); (b) any consolidation or merger or combination
to which the Company is a party other than a merger in which the Company is the
continuing corporation and which does not result in any reclassification of, or
change (other than in par value, or from par value to no par value, or from no
par value to par value, or as a result of a subdivision or combination) in,
outstanding shares of Common Stock; or (c) any sale or conveyance as an
entirety or substantially as an entirety of the property and assets of the
Company, directly or indirectly, to any person, then the Company, or such
successor, purchasing or transferee corporation, as the case may be, shall, as
a condition precedent to such reclassification, change, combination,
consolidation, merger, sale or conveyance, execute and deliver to the Trustee a
supplemental indenture providing that the Holder of each Security then
outstanding shall have the right to convert such Security into Cash and, with
respect to the portion of the Conversion Obligation in excess (if any) of the
principal amount of Securities being converted, the kind and amount of shares
of stock and other securities and property (including Cash) receivable upon
such reclassification, change, combination, consolidation, merger, sale or
conveyance by a holder of the number of shares of Common Stock deliverable upon
conversion of such Security immediately prior to such reclassification, change,
combination, consolidation, merger, sale or conveyance.  For purposes of
the foregoing, if holders of the Common Stock receive or have the right to
receive more than one form of consideration in connection with such
reclassification, change, combination, consolidation, merger, sale or
conveyance, then the Company shall make adequate provisions to give Holders of
the Securities, treated as a single class, a reasonable opportunity to elect
the form of such consideration for purposes of determining the composition of
consideration received, provided
that once the election is made, it shall apply to all Holders of Securities
after the effective time of the transaction. 
Such supplemental indenture shall provide for adjustments of the
Conversion Price which shall be as nearly equivalent as may be practicable to
the adjustments of the Conversion Price provided for in this
Article 5.  If, in the case of any such consolidation, merger,
combination, sale or conveyance, the stock or other securities and property
(including Cash) receivable thereupon by a holder of Common Stock include
shares of stock or other securities and property of a person other than the successor,
purchasing or transferee corporation, as the case may be, in such
consolidation, merger, combination, sale or conveyance, then such supplemental
indenture shall also be executed by such other person and shall contain such
additional provisions to protect the interests of the Holders of the Securities
as the Board of Directors shall reasonably consider necessary by reason of the
foregoing.  The provisions of this Section 5.11 shall similarly apply
to successive reclassifications, changes, combinations, consolidations,
mergers, sales or conveyances.  The
Trustee has no duty to determine whether a supplemental indenture under this
Section 5.11 need be entered into.

In the event the Company shall execute a supplemental
indenture pursuant to this Section 5.11, the Company shall promptly file
with the Trustee (x) an Officers’ Certificate 

 45
 

 

briefly stating the
reasons therefor, the kind or amount of shares of stock or other securities or
property (including Cash) receivable by Holders of the Securities upon the
conversion of their Securities after any such reclassification, change,
combination, consolidation, merger, sale or conveyance, any adjustment to be
made with respect thereto and that all conditions precedent have been complied
with and (y) an Opinion of Counsel that all conditions precedent have been
complied with, and shall promptly mail notice thereof to all Holders.

Section 5.12.   Disclaimer.

Nether the Trustee nor any Conversion Agent (other
than the Company or an Affiliate of the Company) shall have any duty to
determine when an adjustment under this Article 5 should be made, how it
should be made or what such adjustment should be, but may accept as conclusive
evidence of that fact or the correctness of any such adjustment, and shall be
protected in relying upon, an Officers’ Certificate, including the Officers’
Certificate with respect thereto, which the Company is obligated to file with
the Trustee (and to deliver a copy thereof to the Conversion Agent) pursuant to
Section 5.10.  Neither the Trustee nor any Conversion Agent (other
than the Company or an Affiliate of the Company) makes any representation as to
the validity or value of any securities or assets issued upon conversion of
Securities, and neither shall be responsible for the Company’s failure to
comply with any provisions of this Article 5.

The Trustee shall not be under any responsibility to
determine the correctness of any provisions contained in any supplemental
indenture executed pursuant to Section 5.11, but may accept as conclusive
evidence of the correctness thereof, and shall be fully protected in relying
upon, the Officers’ Certificate with respect thereto which the Company is
obligated to file with the Trustee pursuant to Section 5.11.

Section 5.13.   Limitation on Adjustments.

(a) The Company shall not take any action that would
result in an adjustment pursuant to the foregoing provisions in this Article 5
without complying with the NASDAQ’s shareholder approval rules.

(b) The Company shall not take any action that would
result in an adjustment pursuant to the foregoing provisions in this Article 5
if that adjustment would reduce the Conversion Price below the then par value
of the shares of Common Stock issuable upon conversion of the Securities.

ARTICLE 6     [RESERVED]

ARTICLE 7     COVENANTS

Section 7.01.   Payment of Securities.

The Company shall promptly make all payments in
respect of the Securities on the dates and in the manner provided in the
Securities and this Indenture.  An installment of principal or interest
shall be considered paid on the date it is due if the Paying Agent (other than
the Company) holds by 11:00 a.m., New York City time, on that date money,
deposited by the

 46
 

 

Company or an Affiliate thereof, sufficient to pay
such installment.  The Company shall (in immediately available funds), to
the fullest extent permitted by law, pay interest on overdue principal
(including premium, if any) and overdue installments of interest at the rate
borne by the Securities per annum.

Payment of the principal of (and premium, if any) and
interest on the Securities shall be made at the office or agency of the Company
maintained for that purpose in New York, New York (which shall initially be The
Bank of New York), or at the Corporate Trust Office of the Trustee 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; provided, however, that
at the option of the Company payment of interest may be made by check mailed to
the address of the Person entitled thereto as such address appears in the
Register; provided, further, that a Holder holding an
aggregate principal amount of the Securities in excess of $2,000,000 will be
paid by wire transfer in immediately available funds at the election of such
Holder if such Holder has provided wire transfer instructions to the Company
(which the Company shall promptly forward to the Trustee and the Paying Agent)
at least 10 Business Days prior to the payment date.

Section 7.02.   SEC Reports.

The Company shall file with the Trustee and the SEC,
and transmit to Holders, such information, documents and other reports and such
summaries thereof, as may be required pursuant to the TIA at the times and in
the manner provided pursuant to the TIA; provided that any such information,
documents or reports required to be filed with the SEC pursuant to Section 13
or 15(d) of the Exchange Act shall, unless such information, documents or
reports are available on the SEC’s EDGAR filing system (or any successor
thereto), be filed with the Trustee within 15 days after the same is so
required to be filed with the SEC.

Delivery of such reports, information and documents to
the Trustee 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 Company’s
compliance with any of its covenants hereunder (as to which the Trustee is
entitled to rely exclusively on Officers’ Certificates).

Section 7.03.   Maintenance of Listing.  

So long as any Securities are outstanding and the
Common Stock is publicly traded, the Company will not voluntarily delist the
Common Stock from NASDAQ or any other U.S. national securities exchange on
which the Common Stock is then listed.

Section 7.04.   Compliance Certificates.

The Company shall deliver to the Trustee, within 90
days after the end of each fiscal year of the Company (beginning with the
fiscal year ending December 31, 2006), an Officers’ Certificate as to the signer’s
knowledge of the Company’s compliance with all conditions and covenants on its
part contained in this Indenture and stating whether or not the signer knows of
any default or Event of Default.  If such signer knows of such a default
or Event of Default, the Officers’ Certificate shall describe the default or
Event of Default and the efforts to remedy the 

 47
 

 

same.  For the
purposes of this Section 7.04, compliance shall be determined without
regard to any grace period or requirement of notice provided pursuant to the
terms of this Indenture.

Section 7.05.   Liquidated
Damages Notice.

In the event that the Company is required to pay Liquidated
Damages to Holders of Securities pursuant to any Registration Rights
Agreement or Section 9.01 hereof, the Company will provide a direction or order
in the form of a written notice (“Liquidated
Damages  Notice”) to the
Trustee (and if the Trustee is not the Paying Agent, the Paying Agent) of the
Company’s obligation to pay Liquidated Damages no later than ten
Business Days prior to the proposed payment date set for the payment of Liquidated
Damages, and the Liquidated Damages Notice shall set forth
the amount of Liquidated Damages to be paid by the Company on such payment date
and direct the Trustee (or, if the Trustee is not the Paying Agent, the Paying
Agent) to make payment to the extent it receives funds from the Company to do
so.  The Trustee shall not at any time be
under any duty or responsibility to any holder of Securities to determine
whether Liquidated Damages are payable, or with respect to the nature, extent,
or calculation of the amount of Liquidated Damages owed, or with respect to the
method employed in such calculation of Liquidated Damages.

Section 7.06.   Rule 144A Information Requirements.

Within the period prior to the expiration of the
holding period applicable to sales of the Securities under Rule 144(k)
under the Securities Act (or any successor provision), the Company covenants
and agrees that it shall, during any period in which it is not subject to Section 13
or 15(d) under the Exchange Act, upon the request of any Holder or beneficial
holder of the Securities or any Common Stock issued upon conversion thereof
bearing a Restricted Security Legend or Restricted Stock Legend, as the case
may be, make available to such Holder or beneficial holder of such Securities
or any Common Stock issued upon conversion thereof in connection with any sale
thereof and any prospective purchaser of Securities or such Common Stock designated
by such Holder or beneficial holder, the information required pursuant to
Rule 144A(d)(4) under the Securities Act and it will take such further
action as any Holder or beneficial holder of such Securities or such Common
Stock may reasonably request, all to the extent required from time to time to
enable such Holder or beneficial holder to sell its Securities or Common Stock
without registration under the Securities Act within the limitation of the exemption
provided by Rule 144A, as such Rule may be amended from time to time.  Upon the request of any Holder or any
beneficial holder of the Securities or such Common Stock, the Company will
deliver to such Holder a written statement as to whether such Holder and
prospective purchaser have complied with such requirements.

Section 7.07.   Further Instruments and Acts.

Upon request of the Trustee, the Company will execute
and deliver such further instruments and do such further acts as may be
reasonably necessary or proper to carry out more effectively the purposes of
this Indenture.

 48
 

 

Section 7.08.   Maintenance of Corporate Existence.

Subject to Article 8, the Company will do or
cause to be done all things necessary to preserve and keep in full force and
effect its corporate existence.

Section 7.09.   Stay, Extension and Usury Laws.

The Company 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 or other law which would prohibit or forgive the Company
from paying all or any portion of the principal of, or premium, if any, or
interest on, the Securities as contemplated herein, wherever enacted, now or at
any time hereafter in force, or which may affect the covenants or the
performance of this Indenture, and the Company (to the extent it may lawfully
do so) hereby expressly waives all benefit or advantage of any such law and
covenants that it will not, by resort to any such law, hinder, delay or impede
the execution of any power herein granted to the Trustee, but will suffer and
permit the execution of every such power as though no such law had been
enacted.

ARTICLE 8     CONSOLIDATION, MERGER, CONVEYANCE, TRANSFER
OR LEASE

Section 8.01.   Company May Consolidate, etc.,
only on Certain Terms.

The Company shall not consolidate with or merge into
any other Person (in a transaction in which the Company is not the surviving
corporation) or convey, transfer or lease its properties and assets substantially
as an entirety to any Person, unless:

(1) in case the Company shall consolidate with or
merge into another Person (in a transaction in which the Company is not the
surviving corporation) or convey, transfer or lease its properties and assets
substantially as an entirety to any Person, the Person formed by such
consolidation or into which the Company is merged or the Person which acquires
by conveyance or transfer, or which leases, the properties and assets of the
Company substantially as an entirety shall be a corporation organized and
validly existing under the laws of the United States of America, any State
thereof or the District of Columbia and shall expressly assume, by an indenture
supplemental hereto, executed and delivered to the Trustee, in form
satisfactory to the Trustee, the due and punctual payment of the principal of,
and premium, if any, and interest on, all the Securities and the performance or
observance of every covenant of this Indenture on the part of the Company to be
performed or observed, and the conversion rights shall be provided for in
accordance with Article 5, by supplemental indenture satisfactory in form
to the Trustee, executed and delivered to the Trustee, by the Person (if other
than the Company) formed by such consolidation or into which the Company shall
have been merged or by the Person which shall have acquired the Company’s
assets;

(2) immediately after giving effect to such
transaction, no Event of Default, and no event which, after notice or lapse of
time or both, would become an Event of Default, shall have happened and be
continuing; and

 49
 

 

(3) the Company has delivered to the Trustee an
Officers’ Certificate and an Opinion of Counsel, each in a form reasonably
satisfactory to the Trustee and stating that such consolidation, merger,
conveyance, transfer or lease and, if a supplemental indenture is required in
connection with such transaction, such supplemental indenture comply with this
Article and that all conditions precedent herein provided for relating to
such transaction have been complied with.

Section 8.02.   Successor Substituted.

Upon any consolidation of the Company with, or merger
of the Company into, any other Person or any conveyance, transfer or lease of
the properties and assets of the Company substantially as an entirety in
accordance with Section 8.01, the successor Person formed by such
consolidation or into which the Company is merged or to which such conveyance,
transfer or lease is made shall succeed to, and be substituted for, and may exercise
every right and power of, the Company under this Indenture with the same effect
as if such successor Person had been named as the Company herein, and
thereafter, except in the case of a lease, the predecessor Person shall be
relieved of all obligations and covenants under this Indenture and the
Securities.

ARTICLE 9     DEFAULT AND REMEDIES

Section 9.01.   Events of Default.

An “Event of Default”
with respect to Securities shall occur if:

(a) the Company defaults in the payment of interest
(including any Liquidated Damages) when the same becomes due and payable and
the default continues for a period of 30 days;

(b) the Company defaults in the payment of any
principal of (including, without limitation, premium, if any, on) any Security
when the same becomes due and payable (whether at maturity, on a Fundamental
Change Purchase Date or otherwise);

(c) the Company defaults in the payment of Cash or
shares of Common Stock (if any) upon conversion of any Security (including any
Additional Shares), when the same becomes due and payable;

(d) the Company fails to comply with any of its other
agreements contained in the Securities or in this Indenture (other than in the
case of a failure to file reports as specified below) and the default continues
for the period and after the notice specified below;

(e) the Company defaults in the payment of the
purchase price of any Security when the same becomes due and payable;

(f) the Company fails to provide on a timely basis
written notice of a Fundamental Change as required by Section 3.01(b);

(g) the Company or any Significant Subsidiary of the
Company fails to pay any Indebtedness at final maturity (either at its stated
maturity or upon acceleration thereof) with
a 

 50
 

 

principal amount then outstanding in excess of $20
million, whether such Indebtedness now exists or shall hereafter be created,
and such Indebtedness is not discharged, or such default in payment or
acceleration is not cured or rescinded after the applicable grace period, if
any, specified in the agreement or Instrument relating to such Indebtedness;

(h) the Company or any Significant Subsidiary of the
Company fails to pay one or more final and non-appealable judgments entered by
a court or courts of competent jurisdiction, the aggregate uninsured or
unbonded portion of which is in excess of $20 million, if the judgments are not
paid, discharged or stayed within 30 days;

(i) the Company or any Significant Subsidiary of the
Company, pursuant to or within the meaning of any Bankruptcy Law:

(i) commences a voluntary case or proceeding;

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

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

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

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

(i) is for relief against the Company or any
Significant Subsidiary of the Company in an involuntary case or proceeding;

(ii) appoints a custodian of the Company or any
Significant Subsidiary of the Company for all or substantially all of the
property of the Company or any such Significant Subsidiary; or

(iii) orders the liquidation of the Company or any
Significant Subsidiary of the Company;

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

The term “Bankruptcy Law”
means Title 11 of the United States Code (or any successor thereto) or any
similar federal or state law for the relief of debtors.  The term “Custodian” means any receiver, trustee, assignee,
liquidator, sequestrator or similar official under any Bankruptcy Law.

A default under clause (d) above is not an Event
of Default until the Trustee notifies the Company, or the Holders of at least
25% in aggregate principal amount of the Securities then outstanding notify the
Company and the Trustee, in writing of the default, and the Company does not
cure the default within 60 days after receipt of such notice. The notice given
pursuant to this 

 51
 

 

Section 9.01 must specify the default, demand
that it be remedied and state that the notice is a “Notice of Default.” 
When any default under this Section 9.01 is cured, it ceases.

Any failure by the Company to file periodic or other
reports in accordance with Section 7.02 shall not constitute an Event of
Default and remedies under this Indenture against the Company for any such
failure shall be limited to liquidated damages as provided in the following
sentence.  If the Company fails to comply
with its obligation under Section 7.02 to file periodic or other reports and
such failure continues for 90 days after notice thereof is given in accordance
with the terms hereof, the Company shall pay liquidated damages to all Holders
at a rate per annum equal to 0.50% of the principal amount of the Securities
from the 90th day following such notice until such breach is cured.  All accrued and unpaid liquidated damages
arising under this paragraph, if any, shall be paid in arrears in Cash to
Holders of the Securities by the Company on the Interest Payment Date on which
interest in respect of the Notes for the same accrual period is paid, to the
Holders receiving such interest.

The Trustee shall not be charged with knowledge of any
Event of Default unless written notice thereof shall have been given to a Trust
Officer at the Corporate Trust Office of the Trustee by the Company, a Paying
Agent, any Holder or any agent of any Holder.

Section 9.02.   Acceleration.

If an Event of Default (other than an Event of Default
specified in clause (i) or (j) of Section 9.01) occurs and is
continuing with respect to any Securities, the Trustee may, by notice to the
Company, or the Holders of at least 25% in aggregate principal amount of the
Securities then outstanding may, by notice to the Company and the Trustee,
declare all unpaid principal to the date of acceleration on the
Securities then outstanding (if not then due and payable) to be due and
payable upon any such declaration, and the same shall become and be immediately
due and payable.  If an Event of Default specified in clause (i) or
(j) of Section 9.01 occurs, all unpaid principal of the Securities
then outstanding shall ipso facto become and be immediately due and payable
without any declaration or other act on the part of the Trustee or any
Holder.  The Holders of a majority in aggregate principal amount of the
Securities then outstanding by notice to the Trustee may rescind an
acceleration of Securities and its consequences if (a) all existing
Events of Default, other than the nonpayment of the principal of the
Securities which has become due solely by such declaration of
acceleration, have been cured or waived; (b) interest which has become due
otherwise than by such declaration of acceleration, has been paid; (c) the
rescission would not conflict with any judgment or decree of a court of
competent jurisdiction; and (d) all payments due to the Trustee and any
predecessor Trustee under Section 10.07 have been made.  No such
rescission shall affect any subsequent default or impair any right consequent
thereto.

Section 9.03.   Other Remedies.

If an Event of Default with respect to Securities
occurs and is continuing, the Trustee may, but shall not be obligated to,
pursue any available remedy by proceeding at law or in equity to collect the
payment of the principal of, or premium, if any, or any interest on, the
Securities or to enforce the performance of any provision of the Securities or
this Indenture.

 52
 

 

The Trustee may maintain a proceeding even if it does
not possess any of the Securities or does not produce any of them in the
proceeding.  A delay or omission by the Trustee or any Holder 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.  No remedy is exclusive of any other remedy.  All
available remedies are cumulative to the extent permitted by law.

Section 9.04.   Waiver of Defaults and Events of
Default.

Subject to Section 9.07 and 12.02, the Holders of
a majority in aggregate principal amount of the Securities then
outstanding by notice to the Trustee may waive an existing default or Event of
Default and its consequence, except a default or Event of Default in the
payment of the principal of, or premium, if any, or interest on, any Security,
a failure by the Company to convert any Securities into Cash or shares of
Common Stock, if any, or any default or Event of Default in respect of any
provision of this Indenture or the Securities which, under Section 12.02,
cannot be modified or amended without the consent of the Holder of each
Security affected.  When a default or Event of Default is waived, it is
cured and ceases.

Section 9.05.   Control by Majority.

The Holders of a majority in aggregate principal
amount of the Securities then outstanding may direct the time, method and place
of conducting any proceeding for 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 this Indenture, that
the Trustee determines may be unduly prejudicial to the rights of another
Holder or the Trustee or that may involve the Trustee in personal liability
unless the Trustee is offered indemnity satisfactory to it; provided, however, that the Trustee may take any other action deemed
proper by the Trustee which is not inconsistent with such direction.

Section 9.06.   Limitations on Suits.

A Holder of a Security may not pursue any remedy with
respect to this Indenture or the Securities (except actions for payment of
overdue principal, premium, if any, or interest or for the conversion of the
Securities pursuant to Article 5) unless:

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

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

(c) such Holder or Holders offer to the Trustee
reasonable indemnity to the Trustee against any loss, liability or expense;

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

 53
 

 

(e) no direction inconsistent with such written
request has been given to the Trustee during such 60-day period by the Holders
of a majority in aggregate principal amount of the Securities then outstanding.

A Holder may not use this Indenture to prejudice the
rights of another Holder or to obtain a preference or priority over such other
Holder, it being understood that the Trustee does not have an affirmative duty
to ascertain whether or not a Holder’s actions or forbearances constitute such
prejudicial use.

Section 9.07.   Rights of Holders to Receive Payment
and to Convert.

Notwithstanding any other provision of this Indenture,
the right of any Holder of a Security to receive payment of the principal of,
premium, if any, and interest on, the Security, on or after the respective due
dates expressed in the Security and this Indenture, to convert such Security in
accordance with Article 5 and to bring suit for the enforcement of any
such payment on or after such respective dates or the right to convert, is
absolute and unconditional and shall not be impaired or affected without the
consent of the Holder.

Section 9.08.   Collection Suit by Trustee.

If an Event of Default in the payment of principal,
premium, if any, or interest specified in clause (a) or (b) of
Section 9.01 occurs and is continuing, the Trustee may recover judgment in
its own name and as trustee of an express trust against the Company or another
obligor on the Securities for the whole amount of principal, premium, if
any, and accrued interest remaining unpaid, 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 9.09.   Trustee May File Proofs of
Claim.

The Trustee may 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 allowed in any judicial proceedings relative to the Company (or
any other obligor on the Securities), its creditors or its property and shall
be entitled and empowered to collect and receive any money or other property
payable or deliverable on any such claims and to distribute the same, 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 10.07, and to the extent that such
payment of the reasonable compensation, expenses, disbursements and advances in
any such proceedings 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 property which the Holders may be
entitled to receive in such proceedings, whether in liquidation or under any
plan of reorganization or arrangement or otherwise.  Nothing herein
contained shall be deemed to authorize the Trustee to authorize or consent to,
or, on behalf of 

 54
 

 

any Holder, to authorize, accept or adopt, any plan of
reorganization, arrangement, adjustment or composition affecting the Securities
or the rights of any Holder thereof or to authorize the Trustee to vote in
respect of the claim of any Holder in any such proceeding.

Section 9.10.   Priorities.

If the Trustee collects any money pursuant to this
Article 9, it shall pay out the money in the following order:

First, to the
Trustee for amounts due under Section 10.07;

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

Third, the balance,
if any, to the Company.

The Trustee may fix a record date and payment date for
any payment to Holders pursuant to this Section 9.10.

Section 9.11.   Undertaking for Costs.

In any suit for the enforcement of any right or remedy
under this Indenture or in any suit against the Trustee for any action taken or
omitted by it as 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 9.11 does not apply to a
suit made by the Trustee, a suit by a Holder pursuant to Section 9.07 or a
suit by Holders of more than 10% in aggregate principal amount of the
Securities then outstanding.

ARTICLE 10    
TRUSTEE

Section 10.01.   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 this Indenture and use the same degree of
care and skill in its exercise as a prudent person would exercise or use under
the circumstances in the conduct of his or her own affairs.

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

(i)
the Trustee need perform only those duties as are specifically set forth in
this Indenture and no others and no implied covenants or obligations shall be
read into this Indenture or the TIA against the Trustee; and

(ii) in the absence of bad faith on its part, the
Trustee may conclusively rely, without investigation as to the truth of the
statements and the correctness of the opinions 

 55

 

expressed therein, upon certificates or opinions
furnished to the Trustee and conforming to the requirements of this Indenture
but need not verify the content thereof. 
The Trustee, however, shall examine any certificates and opinions which
by any provision hereof are specifically required to be delivered to the
Trustee to determine whether or not they conform to the requirements of this
Indenture.

(c) The Trustee may not be relieved from liability 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
subsection (b) of this Section 10.01;

(ii) the Trustee shall not be liable for any error of
judgment made in good faith by a Trust 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 Section 9.02, 9.04 or 9.05.

(d) No provision of this Indenture shall require the
Trustee to expend or risk its own funds or otherwise incur any financial
liability in the performance of any of its duties hereunder or in the exercise
of any of its rights or powers unless the Trustee shall have received adequate
indemnity in its opinion against potential costs and liabilities incurred by it
relating thereto.

(e) Every provision of this Indenture that in any way
relates to the Trustee is subject to subsections (a), (b), (c) and (d) of
this Section 10.01.

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

Section 10.02.   Rights of Trustee.

Subject to Section 10.01:

(a) The Trustee may rely conclusively on 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.

(b) Before the Trustee acts or refrains from acting,
it may require an Officers’ Certificate or an Opinion of Counsel or both, which
shall conform to Section 13.04(b).  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.

(c) The Trustee may execute any of the trusts or
powers hereunder or perform any duties hereunder either directly or by or
through agents, attorneys, or independent contractors 

 56
 

 

and shall not be responsible for any misconduct or
negligence on the part of any agent, attorney or independent contractor
appointed with due care.

(d) The Trustee shall not be liable for any action it
takes or omits to take in good faith which it believes to be authorized or
within its rights or powers.

(e) The Trustee may consult with counsel of its
selection, and the advice or opinion of such counsel as to matters of law shall
be full and complete authorization and protection in respect of any such action
taken, omitted or suffered by it hereunder in good faith and in accordance with
the advice or opinion of such counsel.

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

(g) The Trustee shall not be bound to make any
investigation into the facts or matters stated in any resolution, certificate,
statement, instrument, opinion, report, notice, request, direction, consent,
order, bond, debenture, note, other evidence of Indebtedness or other paper or
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
shall determine to make such further inquiry or investigation, it shall be
entitled to examine the books, records and premises of the Company, personally
or by agent or attorney at the sole cost of the Company, and shall incur no
liability or additional liability of any kind by reason of such inquiry or
investigation.

(h) The Trustee shall not be deemed to have knowledge
of any Default or Event of Default unless a Trust Officer of the Trustee has
actual knowledge thereof or unless written notice of any event which is in fact
such a default is received by the Trustee at the Corporate Trust Office, and
such notice references the Securities and this Indenture.  The Trustee shall not be charged with the
knowledge of the Company’s obligation to pay Liquidated Damages, or the
cessation of such obligation, unless the Trustee receives written notice
thereof from the Company or any Holder.

(i) The rights, privileges, protections, immunities
and benefits given to the Trustee, including, without limitation, its right to
be indemnified, are extended to, and shall be enforceable by, the Trustee in
each of its capacities hereunder, and to each agent, custodian and other Person
employed to act hereunder (including, but not limited to, the Paying Agent or
Conversion Agent).

(j) Unless otherwise specifically provided in this
Indenture, any demand, request, direction or notice from the Company shall be
sufficiently evidenced by a written order signed by one Officer of the Company.

(k) In no event shall the Trustee be responsible or
liable for special, indirect, or consequential loss or damage of any kind  whatsoever (including, but not limited to,
loss of 

 57
 

 

profit) irrespective of whether the Trustee has been
advised of the likelihood of such loss or damage and regardless of the form of
action.

(l) The Trustee may request that the Company deliver a
certificate setting forth the names of individuals and/or titles of officers
authorized at such time to take specified actions pursuant to this Indenture.

Section 10.03.   Individual Rights of Trustee.

The Trustee in its individual or any other capacity
may become the owner or pledgee of Securities and may otherwise deal with the
Company or an Affiliate of the Company with the same rights it would have if it
were not Trustee.  Any Agent may do the same with like rights. 
However, the Trustee is subject to Section 10.10 and 10.11.

Section 10.04.   Trustee’s Disclaimer.

The Trustee makes no representation as to the validity
or adequacy of this Indenture or the Securities, it shall not be accountable
for the Company’s use of the proceeds from the Securities, and it shall not be
responsible for any statement herein or in the Securities or any other document
in connection with the sale of the Securities or pursuant to this Indenture
other than its certificate of authentication.

Section 10.05.   Notice of Default or Events of
Default.

If a default or an Event of Default occurs and is
continuing and if it is known to the Trustee, the Trustee shall mail to each
Holder notice of the default or Event of Default within 90 days after it
becomes known to the Trustee.  However,
the Trustee may withhold the notice if and so long as a committee of its Trust
Officers in good faith determines that withholding notice is in the interests
of Holders, except in the case of a default or an Event of Default in payment
of the principal of, or interest or premium, if any, on any Security, including
the failure to make Cash payments due upon conversion.

Section 10.06.   Reports by Trustee to Holders.

If such report is required by TIA Section 313,
within 60 days after each May 15, beginning with the May 15 following
the date of this Indenture, the Trustee shall mail to each Holder a brief
report dated as of such May 15 that complies with TIA
Section 313(a).  The Trustee also shall comply with TIA
Section 313(b)(2) and (c).

A copy of each report at the time of its mailing to
Holders shall be mailed to the Company and filed with the SEC and each stock
exchange, if any, on which the Securities are listed.  The Company shall
notify the Trustee whenever the Securities become listed on any stock exchange
or listed or admitted to trading on any quotation system and any changes in the
stock exchanges or quotation systems on which the Securities are listed or
admitted to trading and of any delisting thereof.

 58
 

 

Section 10.07.   Compensation and Indemnity.

The Company shall pay to the Trustee from time to time
such compensation (as agreed to from time to time by the Company and the Trustee
in writing) for its services (which compensation shall not be limited by any
provision of law in regard to the compensation of a trustee of an express
trust).  The Company shall reimburse the Trustee upon request for all
reasonable disbursements, expenses and advances incurred or made by it. 
Such expenses may include the reasonable compensation, disbursements and
expenses of the Trustee’s agents and counsel.

The Company shall indemnify the Trustee or any
predecessor Trustee (which for purposes of this Section 10.07 shall
include its officers, directors, employees and agents) for, and hold it
harmless against, any and all loss, liability or expense, including taxes
(other than taxes based upon, measured by or determined by the income of the
Trustee), including reasonable legal fees and expenses, incurred by it in
connection with the acceptance or administration of its duties under this
Indenture or any action or failure to act as authorized or within the
discretion or rights or powers conferred upon the Trustee hereunder, including
the reasonable costs and expenses of the Trustee and its counsel in defending
itself against any claim or liability in connection with the exercise or
performance of any of its powers or duties hereunder.  The Trustee shall
notify the Company promptly of any claim asserted against the Trustee for which
it may seek indemnity.  The Company need not pay for any settlement
without its written consent, which shall not be unreasonably withheld.

The Company need not reimburse the Trustee for any
expense or indemnify it against any loss or liability incurred by it resulting
from its gross negligence or bad faith.

To secure the Company’s payment obligations in this
Section 10.07, the Trustee shall have a lien prior to the Securities as to
all money or property held or collected by the Trustee for any amount owing it
or any predecessor Trustee pursuant to this Section 10.07, except such money or
property held in trust for the benefit of holders of particular Securities.  The obligations of the Company under this
Section 10.07 shall survive the satisfaction and discharge of this
Indenture or the resignation or removal of the Trustee.

When the Trustee incurs expenses or renders services
after an Event of Default specified in clause (i) or (j) of Section 9.01
occurs, the expenses and the compensation for the services are intended to
constitute expenses of administration under any Bankruptcy Law.  The
provisions of this Section shall survive the termination of this
Indenture.

Section 10.08.   Replacement of Trustee.

The Trustee may resign by so notifying the
Company.  The Holders of a majority in aggregate principal amount of the
Securities then outstanding may remove the Trustee by so notifying the Trustee
and may, with the Company’s written consent, appoint a successor Trustee. 
The Company may remove the Trustee if:

(a) the Trustee fails to comply with
Section 10.10;

 59
 

 

(b) the Trustee is adjudged a bankrupt or an
insolvent;

(c) a receiver or other 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 Company shall promptly
appoint a successor Trustee.  The resignation or removal of a Trustee
shall not be effective until a successor Trustee shall have delivered the
written acceptance of its appointment as described below.

If a successor Trustee does not take office within 45
days after the retiring Trustee resigns or is removed, the retiring Trustee,
the Company or the Holders of 10% in principal amount of the Securities then
outstanding may petition any court of competent jurisdiction for the
appointment of a successor Trustee at the expense of the Company.

If the Trustee fails to comply with
Section 10.10, any Holder 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 Company. 
Immediately after that, the retiring Trustee shall, upon payment of any fees
and expenses due and owing to it hereunder, transfer all property held by it as
Trustee to the successor Trustee and be released from its obligations (exclusive
of any liabilities that the retiring Trustee may have incurred while acting as
Trustee) hereunder, 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 this Indenture.  A successor Trustee shall
mail notice of its succession to each Holder.

A retiring Trustee shall not be liable for the acts or
omissions of any successor Trustee after its succession.

Notwithstanding replacement of the Trustee pursuant to
this Section 10.08, the Company’s obligations under Section 10.07
shall continue for the benefit of the retiring Trustee.

Section 10.09.   Successor Trustee by Merger, etc.

If the Trustee consolidates with, merges or converts
into, or transfers all or substantially all of its corporate trust assets
(including the administration of this Indenture) to, another corporation, the
resulting, surviving or transferee corporation, without any further act, shall
be the successor Trustee, provided such transferee corporation shall qualify
and be eligible under Section 10.10.  Such successor Trustee shall
promptly mail notice of its succession to the Company and each Holder.

Section 10.10.   Eligibility; Disqualification.

The Trustee shall always satisfy the requirements of
paragraphs (1), (2) and (5) of TIA Section 310(a).  The
Trustee (or its parent holding company) shall have a combined capital and
surplus of at least $50,000,000.  If at any time the Trustee shall cease
to satisfy any such 

 60
 

 

requirements, it shall resign immediately in the
manner and with the effect specified in this Article 10.  The Trustee
shall be subject to the provisions of TIA Section 310(b).  Nothing
herein shall prevent the Trustee from filing with the SEC the application
referred to in the penultimate paragraph of TIA Section 310(b).

Section 10.11.   Preferential Collection of Claims
Against Company.

The Trustee shall comply with 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.

Section 10.12.   Trustee or Agents May Hold
Securities

The Trustee, any Paying Agent, any Registrar or any
other agent of the Company, in its individual or any other capacity, may become
the owner or pledgee of Securities and, subject to Section 10.11, may otherwise
deal with the Company with the same rights it would have if it were not
Trustee, Paying Agent, Registrar or such other agent.

ARTICLE 11     SATISFACTION AND DISCHARGE

Section 11.01.   Satisfaction and Discharge.

(a) This Indenture shall cease to be of further
effect, and the Trustee, on demand of and at the expense of the Company, shall
execute proper instruments acknowledging satisfaction and discharge of this
Indenture, when

(i) all Securities theretofore authenticated and
delivered (other than (i) Securities which have been destroyed, lost
or stolen and which have been replaced or paid as provided in Section 2.07
and (ii) Securities for whose payment money has theretofore been
deposited in trust and thereafter repaid to the Company as provided in
Section 11.03) have been delivered to the Trustee for cancellation;

(ii) the Company has paid or caused to be paid all
other sums payable hereunder by the Company; and

(iii) the Company has 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 this Indenture have been complied with.

Notwithstanding the satisfaction and discharge of this
Indenture, the obligations of the Company to the Trustee under
Section 10.07 shall survive.

(b) The Company may discharge its obligations to pay
principal of, and interest, and premium, if any, on the Securities when
all Securities not theretofore delivered to the Trustee for cancellation

(i) have become due and payable, or

 61
 

 

(ii) will become due and payable at the Final Maturity
Date within one year,

and the Company, in the case of clause (i) or
(ii) above, has irrevocably, subject to the limitations set forth in the
following sentence, deposited or caused to be irrevocably, subject to the
limitations set forth in the following sentence, deposited with the Trustee or
a Paying Agent (other than the Company or any of its Affiliates) as trust funds
in trust for the purpose cash in an amount sufficient to pay and discharge the
entire indebtedness on such Securities not theretofore delivered to the Trustee
for cancellation, for principal, premium, if any, interest, to the date of such
deposit (in the case of Securities which have become due and payable) or to the
Final Maturity Date; provided, however, that the foregoing shall not
discharge the Company’s obligation to effect conversion, registration of
transfer or exchange of Securities in accordance with the terms of this Indenture
or affect the obligations of the Company to the Trustee under Section 10.07
hereof.

Section 11.02.   Application of Trust Money.

Subject to the provisions of Section 11.03, the
Trustee or a Paying Agent shall hold in trust, for the benefit of the Holders
of Securities, all money deposited with it pursuant to Section 11.01(b)
with respect to Securities and shall apply the deposited money in accordance
with this Indenture and the Securities to the payment of the principal of, and
any interest and premium on, the Securities.

Section 11.03.   Repayment to Company.

The Trustee and each Paying Agent shall promptly pay
to the Company upon request any excess money (i) deposited with them
pursuant to Section 11.01(b) and (ii) held by them at any time.

The Trustee and each Paying Agent shall pay to the
Company upon request any money held by them for the payment of principal,
premium, if any, or interest that remains unclaimed for two years after a right
to such money has matured; provided, however, that
the Trustee or such Paying Agent, before being required to make any such
payment, may at the expense of the Company cause to be mailed to each Holder
entitled to such money notice that such money remains unclaimed and that after
a date specified therein, which shall be at least 30 days from the date of such
mailing, any unclaimed balance of such money then remaining will be repaid to
the Company.  After payment to the Company, Holders entitled to money must
look to the Company for payment as general creditors unless an applicable
abandoned property law designates another person.

Section 11.04.   Reinstatement.

If the Trustee or any Paying Agent is unable to apply
any money in accordance with Section 11.02 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 Company’s obligations under this Indenture and the Securities shall be
revived and reinstated as though no deposit had occurred pursuant to
Section 11.01(b) until such time as the Trustee or such Paying Agent
is permitted to apply all such money in accordance with 

 62
 

 

Section 11.02; provided,
however, that, if the Company has
made any payment of the principal of, or interest or premium, if any, on, any
Securities because of the reinstatement of its obligations, the Company shall
be subrogated to the rights of the Holders of such Securities to receive any
such payment from the money held by the Trustee or such Paying Agent.

ARTICLE 12     AMENDMENTS, SUPPLEMENTS AND WAIVERS

Section 12.01.   Without Consent of Holders.

The Company, when authorized by a resolution of the
Board of Directors, and the Trustee may amend or supplement the Indenture or
the Securities without notice to or consent of any Holder:

(a) to comply with Section 5.11 and 8.01;

(b) to cure any ambiguity, or correct any defect or
inconsistency; provided that any amendment or supplement to cure any ambiguity
or correct any defect or inconsistency in the Indenture or the Securities that
is made solely to conform the provisions of the Indenture and the Securities to
the descriptions thereof contained in the offering memorandum relating to the
Securities dated October 24, 2006, will be deemed not to adversely affect the
rights of any Holder;

(c) to make any other change that does not adversely
affect the rights of any Holder;

(d) to comply with the provisions of the TIA;

(e) to add to the covenants of the Company for the
equal and ratable benefit of the Holders or to surrender any right, power or
option conferred upon the Company;

(f) to appoint a successor Trustee; or

(g) to provide for the issuance of Additional
Securities as permitted by Section 2.16, which will have terms substantially
identical to the other outstanding Securities except as specified in Section
2.16, and which will be treated, together with any other outstanding
Securities, as a single issue of securities.

Section 12.02.   With Consent of Holders.

The Company and the Trustee may amend or supplement
the Securities or this Indenture with the written consent of the Holders of at
least a majority in aggregate principal amount of the Securities then
outstanding.  The Holders of at least a
majority in aggregate principal amount of the Securities then outstanding may
waive compliance in a particular instance by the Company with any provision of
the Securities or this Indenture without notice to any Holder.  However, notwithstanding the foregoing but
subject to Section 12.04, without the written consent of each Holder
affected, an amendment, supplement or waiver, including a waiver pursuant to
Section 9.04, may not:

 63
 

 

(a) change the stated maturity of the principal of, or
the date any installment of interest (including any Liquidated Damages) is due
on, any Security;

(b) reduce the principal amount of, or any premium or
interest (including any Liquidated Damages) on, any Security;

(c) reduce the amount of principal payable upon
acceleration of the maturity of any Security;

(d) change the place or currency of payment of
principal of, or any premium, if any, or interest (including any Liquidated
Damages) on, any Security;

(e) impair the right to institute suit for the
enforcement of any payment on, or with respect to, any Security;

(f) modify the provisions with respect to the purchase
right of Holders pursuant to Article 3 upon a Fundamental Change in a
manner adverse to the Holders of Securities;

(g) modify the provisions of this Indenture with
respect to conversion of the Securities in a manner adverse to the Holders of
Securities;

(h) reduce the percentage of the aggregate principal
amount of the outstanding Securities whose Holders must consent to a
modification or amendment;

(i) reduce the percentage of the aggregate principal
amount of the outstanding Securities necessary for the waiver of compliance
with certain provisions of this Indenture or the waiver of certain defaults
under this Indenture; and

(j) modify any of the provisions of this
Section or Section 9.04, except to increase any such percentage or to
provide that certain provisions of this Indenture cannot be modified or waived
without the consent of the Holder of each outstanding Security affected
thereby.

It shall not be necessary for the consent of the
Holders under this Section 12.02 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 12.02 becomes effective, the Company shall mail to the Holders
affected thereby a notice briefly describing the amendment, supplement or
waiver.  Any failure of the Company to mail such notice, or any defect
therein, shall not, however, in any way impair or affect the validity of any
such amendment, supplement or waiver.

Section 12.03.   Compliance with Trust Indenture Act.

Every amendment to or supplement of this Indenture or
the Securities shall comply with the TIA as in effect at the date of such
amendment or supplement.

 64

 

Section 12.04.    Revocation and Effect of Consents.

 

Until an amendment, supplement or waiver becomes
effective, a consent to it by a Holder is a continuing consent by the Holder
and every subsequent Holder of a Security or portion of a Security that evidences
the same debt as the consenting Holder’s Security, even if notation of the
consent is not made on any Security.  However, any such Holder or
subsequent Holder may revoke the consent as to its Security or portion of a
Security if the Trustee receives the notice of revocation before the date the
amendment, supplement or waiver becomes effective.

After an amendment, supplement or waiver becomes
effective, it shall bind every applicable Holder, unless it makes a change
described in any of clauses (a) through (l) of Section 12.02.  In that case the amendment, supplement or
waiver shall bind each Holder of a Security who has consented to it and every
subsequent Holder of a Security or portion of a Security that evidences the
same debt as the consenting Holder’s Security.

Section 12.05.    Notation on or Exchange of Securities.

 

If an amendment, supplement or waiver changes the
terms of a Security, the Trustee may require the Holder of the Security to
deliver it to the Trustee.  The Trustee may place an appropriate notation
on the Security about the changed terms and return it to the Holder. 
Alternatively, if the Company or the Trustee so determines, the Company in
exchange for the Security shall issue and the Trustee shall authenticate a new
Security that reflects the changed terms.

Section 12.06.    Trustee to Sign Amendments, etc.

 

The Trustee shall sign any amendment or supplemental
indenture authorized pursuant to this Article 12 if the amendment or
supplemental indenture does not adversely affect the rights, duties,
liabilities or immunities of the Trustee.  If it does, the Trustee may, in
its sole discretion, but need not sign it.  In signing or refusing to sign
such amendment or supplemental indenture, the Trustee shall be entitled to
receive, and, subject to Section 10.01, shall be fully protected in
relying upon, an Officers’ Certificate (accompanied by a resolution of the
Board of Directors of the Company) and an Opinion of Counsel in accordance with
Section 13.04 hereof stating that such amendment or supplemental indenture is
authorized or permitted by this Indenture.  The Company may not sign an
amendment or supplement indenture until the Board of Directors approves it.

Section 12.07.    Effect of Supplemental Indentures.

 

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

 65
 

 

 

ARTICLE 13     MISCELLANEOUS

Section 13.01.    Trust Indenture Act Controls.

 

If any provision of this Indenture limits, qualifies
or conflicts with the duties imposed by any of Sections 310 to 317, inclusive,
of the TIA through operation of Section 318(c) thereof, such imposed
duties shall control.

Section 13.02.    Notices.

 

Any demand, authorization, notice, request, consent or
communication shall be given in writing and delivered in person or mailed by
first-class mail, postage prepaid, addressed as follows or transmitted by
facsimile transmission (confirmed by delivery in person or mail by first-class
mail, postage prepaid, or by guaranteed overnight courier) to the following
facsimile numbers:

If to the Company, to:

United Therapeutics Corporation

1110 Spring Street

Silver Spring, Maryland 20910

Attention:  Chief Financial Officer

Facsimile No.:  (301) 608-9291

if to the Trustee, to:

The Bank of New York

101 Barclay Street, 8 West

New York, New York 10286

Attention:  Corporate Trust
Administration

Facsimile No.:  (212) 815-8707

Such notices or communications shall be effective when
received.

The Company or the Trustee by notice to the other may
designate additional or different addresses for subsequent notices or
communications.

Any notice or communication mailed to a Holder shall
be mailed by first-class mail or delivered by an overnight delivery service to
it at its address shown on the register kept by the Primary Registrar.

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 to
a Holder is mailed in the manner provided above, it is duly given, whether or
not the addressee receives it.

 66
 

 

 

Section 13.03.    Communications by Holders with Other Holders.

 

Holders may communicate pursuant to TIA
Section 312(b) with other Holders with respect to their rights under this
Indenture or the Securities.  The
Company, the Trustee, the Registrar and any other person shall have the
protection of TIA Section 312(c).

Section 13.04.    Certificate and Opinion as to
Conditions Precedent.

 

(a)           Upon any request or application by
the Company to the Trustee to take any action under this Indenture, the Company
shall furnish to the Trustee:

(i)            an Officers’ Certificate stating
that, in the opinion of the signers, all conditions precedent (including any
covenants, compliance with which constitutes a condition precedent), if any,
provided for in this Indenture relating to the proposed action have been
complied with; and

(ii)           an Opinion of Counsel stating that,
in the opinion of such counsel, all such conditions precedent (including any
covenants, compliance with which constitutes a condition precedent) have been
complied with.

(b)           Each Officers’ Certificate and
Opinion of Counsel with respect to compliance with a condition or covenant
provided for in this Indenture shall include:

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

(ii)           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;

(iii)          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 complied with; and

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

provided, however, that
with respect to matters of fact an Opinion of Counsel may rely on an Officers’
Certificate or certificates of public officials.

Section 13.05.    Record Date for Vote or Consent of
Securityholders.

 

The Company (or, in the event deposits have been made
pursuant to Section 11.01, the Trustee) may set a record date for purposes
of determining the identity of Holders entitled to vote or consent to any
action by vote or consent authorized or permitted under this Indenture, which
record date shall not be more than 30 days prior to the date of the
commencement of solicitation of such action.  Notwithstanding the
provisions of Section 12.04, if a record date is fixed, those persons who
were Holders of Securities at the close of business on such record date (or
their duly 

 67
 

 

designated proxies), and
only those persons, shall be entitled to take such action by vote or consent or
to revoke any vote or consent previously given, whether or not such persons
continue to be Holders after such record date.

Section 13.06.    Rules by Trustee, Paying Agent, Registrar
and Conversion Agent.

 

The Trustee may make reasonable rules (not
inconsistent with the terms of this Indenture) for action by or at a meeting of
Holders.  Any Registrar, Paying Agent or Conversion Agent may make
reasonable rules for its functions.

Section 13.07.    Legal Holidays.

 

A “Legal Holiday”
is a Saturday, Sunday or a day on which state or federally chartered banking
institutions in New York, New York or the state in which the Corporate Trust
Office is located are not required to be open.  If a payment date is a
Legal Holiday, payment shall be made on the next succeeding day that is not a
Legal Holiday, and no interest shall accrue for the intervening period. 
If a regular record date is a Legal Holiday, the record date shall not be
affected.

Section 13.08.    Governing Law.

 

This Indenture and the Securities shall be governed
by, and construed in accordance with, the laws of the State of New York without
giving effect to applicable principles of conflicts of law to the extent that
the application of the laws of another jurisdiction would be required thereby.

Section 13.09.    No Adverse Interpretation of Other
Agreements.

 

This Indenture may not be used to interpret another
indenture, loan or debt agreement of the Company or a Subsidiary of the
Company.  Any such indenture, loan or debt agreement may not be used to
interpret this Indenture.

Section 13.10.    No Recourse against Others.

 

All liability described in paragraph 15 of the
Securities of any director, officer, employee or shareholder, as such, of the
Company is waived and released.

Section 13.11.    Successors.

 

All agreements of the Company in this Indenture and
the Securities shall bind its successors. 
All agreements of the Trustee in this Indenture shall bind its
successors.

Section 13.12.    Multiple Counterparts.

 

The parties may sign multiple counterparts of this
Indenture.  Each signed counterpart shall be deemed an original, but all
of them together represent the same agreement.

 68
 

 

 

Section 13.13.    Severability.

 

In case any provisions in this Indenture or in the
Securities 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 13.14.    Table of Contents, Headings, etc.

 

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

Section 13.15.    Qualification of Indenture.

 

The Company shall qualify this Indenture under the TIA
in accordance with the terms and conditions of the Registration Rights
Agreement entered into on the date hereof and shall pay all reasonable costs
and expenses (including attorneys’ fees and expenses for the Company and the
Trustee) incurred in connection therewith, including, but not limited to, costs
and expenses of qualification of the Indenture and the Securities and printing
this Indenture and the Securities.  The
Trustee shall be entitled to receive from the Company any such Officers’
Certificates, Opinions of Counsel or other documentation as it may reasonably
request in connection with any such qualification of this Indenture under the
TIA.

Section 13.16.    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.

[SIGNATURE PAGE
FOLLOWS]

 69
 

 

 

IN WITNESS WHEREOF, the
parties hereto have hereunto set their hands as of the date and year first
above written.

	
  

  	
   

  	
  UNITED THERAPEUTICS CORPORATION

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
   

  	
  /s/ JOHN FERRARI

  
	
   

  	
   

  	
   

  	
   

  	
  Name: John Ferrari

  
	
   

  	
   

  	
   

  	
   

  	
  Title:  Chief Financial Officer and
  Treasurer

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  THE BANK OF NEW YORK,

  
	
   

  	
   

  	
  as Trustee

  
	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  By:

  	
   

  	
  /s/ CHERYL L. CLARKE

  
	
   

  	
   

  	
   

  	
   

  	
  Name: Cheryl L. Clarke

  
	
   

  	
   

  	
   

  	
   

  	
  Title:  Vice President

  
						

 

 70

 

SCHEDULE
4.02

The following
table sets forth the increase in the Conversion Rate, expressed as a number of
Additional Shares to be received per $1,000 principal amount of Securities:

	
   

  	
   

  	
  Stock price

  	
   

  
	
  Effective date

  	
   

  	
  $62.17

  	
   

  	
  $65.00

  	
   

  	
  $70.00

  	
   

  	
  $75.23

  	
   

  	
  $80.00

  	
   

  	
  $85.00

  	
   

  	
  $90.00

  	
   

  	
  $100.00

  	
   

  	
  $115.00

  	
   

  	
  $130.00

  	
   

  	
  $150.00

  	
   

  	
  $175.00

  	
   

  	
  $200.00

  	
   

  	
  $225.00

  	
   

  	
  $250.00

  	
   

  
	
  October
  30, 2006

  	
   

  	
  2.79

  	
   

  	
  2.79

  	
   

  	
  2.49

  	
   

  	
  2.12

  	
   

  	
  1.85

  	
   

  	
  1.61

  	
   

  	
  1.41

  	
   

  	
  1.09

  	
   

  	
  0.76

  	
   

  	
  0.54

  	
   

  	
  0.35

  	
   

  	
  0.21

  	
   

  	
  0.13

  	
   

  	
  0.07

  	
   

  	
  0.00

  	
   

  
	
  October
  15, 2007

  	
   

  	
  2.79

  	
   

  	
  2.79

  	
   

  	
  2.53

  	
   

  	
  2.15

  	
   

  	
  1.85

  	
   

  	
  1.60

  	
   

  	
  1.39

  	
   

  	
  1.05

  	
   

  	
  0.71

  	
   

  	
  0.49

  	
   

  	
  0.31

  	
   

  	
  0.18

  	
   

  	
  0.10

  	
   

  	
  0.06

  	
   

  	
  0.00

  	
   

  
	
  October
  15, 2008

  	
   

  	
  2.79

  	
   

  	
  2.79

  	
   

  	
  2.53

  	
   

  	
  2.11

  	
   

  	
  1.80

  	
   

  	
  1.53

  	
   

  	
  1.31

  	
   

  	
  0.96

  	
   

  	
  0.62

  	
   

  	
  0.41

  	
   

  	
  0.24

  	
   

  	
  0.13

  	
   

  	
  0.07

  	
   

  	
  0.03

  	
   

  	
  0.00

  	
   

  
	
  October
  15, 2009

  	
   

  	
  2.79

  	
   

  	
  2.79

  	
   

  	
  2.43

  	
   

  	
  1.98

  	
   

  	
  1.64

  	
   

  	
  1.36

  	
   

  	
  1.13

  	
   

  	
  0.79

  	
   

  	
  0.47

  	
   

  	
  0.29

  	
   

  	
  0.15

  	
   

  	
  0.06

  	
   

  	
  0.03

  	
   

  	
  0.01

  	
   

  	
  0.00

  	
   

  
	
  October
  15, 2010

  	
   

  	
  2.79

  	
   

  	
  2.74

  	
   

  	
  2.13

  	
   

  	
  1.63

  	
   

  	
  1.28

  	
   

  	
  1.00

  	
   

  	
  0.78

  	
   

  	
  0.47

  	
   

  	
  0.22

  	
   

  	
  0.11

  	
   

  	
  0.04

  	
   

  	
  0.01

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  
	
  October 15, 2011

  	
   

  	
  2.77

  	
   

  	
  2.08

  	
   

  	
  0.99

  	
   

  	
  0.21

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  	
  0.00

  	
   

  

 

 S-1

EXHIBIT
A

[FORM
OF FACE OF SECURITY]

[UNLESS THIS CERTIFICATE
IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A
NEW YORK CORPORATION (“DTC”), TO UNITED THERAPEUTICS CORPORATION (THE “COMPANY”)
OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY
CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN 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)

[THIS
SECURITY AND THE SHARES OF UNITED THERAPEUTICS CORPORATION (THE “COMPANY”)
COMMON STOCK (“COMMON STOCK”) ISSUABLE UPON CONVERSION OF THIS SECURITY HAVE
NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES
ACT”), OR ANY STATE SECURITIES LAWS. 
NEITHER THIS SECURITY, THE SHARES OF COMMON STOCK ISSUABLE UPON
CONVERSION OF THIS SECURITY NOR ANY INTEREST OR PARTICIPATION HEREIN OR THEREIN
MAY BE REOFFERED, SOLD, ASSIGNED, TRANSFERRED, PLEDGED, ENCUMBERED OR OTHERWISE
DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS SUCH TRANSACTION IS
EXEMPT FROM, OR NOT SUBJECT TO, REGISTRATION.] (2)

[THE
HOLDER OF THIS SECURITY, BY ITS ACCEPTANCE HEREOF, AGREES TO OFFER, SELL OR
OTHERWISE TRANSFER SUCH SECURITY, PRIOR TO THE DATE (THE “RESALE RESTRICTION
TERMINATION DATE”) THAT IS TWO YEARS AFTER THE LATER OF THE ORIGINAL ISSUE DATE
HEREOF AND THE LAST DATE ON WHICH THE COMPANY OR ANY AFFILIATE OF THE COMPANY
WAS THE OWNER OF THIS SECURITY (OR ANY PREDECESSOR OF SUCH SECURITY) ONLY (A)
TO THE COMPANY OR ANY SUBSIDIARY THEREOF, (B) FOR SO LONG AS THE SECURITIES ARE
ELIGIBLE FOR RESALE PURSUANT TO RULE 144A, TO A PERSON IT REASONABLY BELIEVES
IS A “QUALIFIED INSTITUTIONAL BUYER” AS DEFINED IN RULE 144A UNDER THE
SECURITIES ACT THAT PURCHASES FOR ITS OWN ACCOUNT OR FOR THE ACCOUNT OF A
QUALIFIED INSTITUTIONAL BUYER TO WHICH NOTICE IS GIVEN THAT THE TRANSFER IS
BEING MADE IN RELIANCE ON RULE 144A, (C) PURSUANT TO A REGISTRATION STATEMENT
THAT HAS BEEN DECLARED EFFECTIVE UNDER THE SECURITIES ACT, OR (D) PURSUANT TO 

(1)             These paragraphs
should be included only if the Security is a Global Security.

(2)             These paragraphs
should be included only if the Security is a Transfer Restricted Security.

 

 

 

ANOTHER
AVAILABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT, SUBJECT
TO THE RIGHTS OF THE COMPANY AND THE WITHIN MENTIONED TRUSTEE PRIOR TO ANY SUCH
OFFER, SALE OR TRANSFER PURSUANT TO CLAUSE (D) TO REQUIRE THE DELIVERY OF AN
OPINION OF COUNSEL, CERTIFICATION AND/OR OTHER INFORMATION SATISFACTORY TO EACH
OF THEM, AND IN EACH OF THE FOREGOING CASES WHERE REGISTRATION OR TRANSFER OF
THIS SECURITY IS REQUIRED, A CERTIFICATE OF TRANSFER IN THE FORM APPEARING ON
THE OTHER SIDE OF THIS SECURITY COMPLETED AND DELIVERED BY THE TRANSFEROR TO
THE TRUSTEE.  THIS LEGEND WILL BE REMOVED
ON OR AFTER THE RESALE RESTRICTION TERMINATION DATE UPON THE REQUEST OF THE
HOLDER.] (2)

[THE
HOLDER OF THIS SECURITY IS ENTITLED TO THE BENEFITS OF A REGISTRATION RIGHTS
AGREEMENT (AS SUCH TERM IS DEFINED IN THE INDENTURE REFERRED TO ON THE REVERSE
HEREOF) AND, BY ITS ACCEPTANCE HEREOF, AGREES TO BE BOUND BY AND TO COMPLY WITH
THE PROVISIONS OF SUCH REGISTRATION RIGHTS AGREEMENT.] (2)

(2)             These paragraphs
should be included only if the Security is a Transfer Restricted Security.

(2)             These paragraphs
should be included only if the Security is a Transfer Restricted Security.

 A-2
 

 

 

UNITED
THERAPEUTICS CORPORATION

CUSIP:                                                                                                                                       No.

0.50% CONVERTIBLE SENIOR NOTES DUE OCTOBER 15, 2011

United Therapeutics Corporation, a Delaware
corporation (the “Company”, which term shall include any successor corporation
under the Indenture referred to on the reverse hereof), promises to pay to Cede
& Co., or registered assigns, the principal sum of
                 dollars
($                 )
on October 15, 2011 [or such greater or lesser amount as is indicated on the
Schedule of Exchanges of Securities on the other side of this Security] (3)

This Security is convertible as specified on the other
side of this Security.  Additional
provisions of this Security are set forth on the other side of this Security.

[SIGNATURE PAGE FOLLOWS]

(3)             This phrase should be
included only if the Security is a Global Security.

 

 A-3
 

 

 

IN WITNESS WHEREOF, the Company has caused this
instrument to be duly executed.

	
  

  	
  UNITED
  THERAPEUTICS

  CORPORATION

  
	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  
	
   

  	
  Name:

  	
   

  
	
   

  	
  Title:

  	
   

  

 

Trustee’s Certificate of
Authentication:  This is one of the
Securities

referred to in the within-mentioned Indenture.

	
  THE BANK OF NEW YORK,

  	
   

  
	
  as Trustee

  	
   

  
	
   

  	
   

  
	
  By:

  	
   

  	
   

  
	
   

  	
  Authorized
  Signatory

  	
   

  

 A-4
 

 

 

[FORM OF REVERSE SIDE OF
SECURITY]

UNITED THERAPEUTICS
CORPORATION

0.50% CONVERTIBLE SENIOR NOTES DUE OCTOBER 15, 2011

1.                                       INTEREST
AMOUNTS

United Therapeutics Corporation, a Delaware
corporation (the “Company”, which term shall include any successor corporation
under the Indenture hereinafter referred to), will pay interest at a rate of
0.50% per annum, on the principal amount of this Security payable as provided
in the Indenture.

2.                                       METHOD
OF PAYMENT

The Company shall pay any interest on this Security to
the person who is the Holder of this Security at the close of business on April
1 or October 1, as the case may be, next preceding the related interest payment
date.  The Holder must surrender this
Security to a Paying Agent to collect payment of principal and premium, if
any.  Interest on the Security will be
paid at a rate of 0.50% per annum, payable semi-annually in arrears on April 15
and October 15 of each year, or if any such day is not a Business Day, the
immediately following Business Day, commencing April 15, 2007.  Interest is computed on the basis of a
360-day year comprised of twelve 30-day months. 
In the event of the maturity, conversion or purchase of the Security by
the Company at the option of the Holder, interest shall cease to accrue on the
Security.  However, the Company will pay
interest on the maturity date to a Holder of record of the Security on the
record date immediately preceding the stated maturity date regardless of
whether such Holder converts the Security.

The Company will pay principal of (and premium, if
any) and interest on this Security in such coin or currency of the United
States of America that at the time of payment is legal tender for payment of
public and private debts.  The Company
may, however, pay principal, premium, if any, and interest in respect of any
Certificated Security by check or wire transfer payable in such money; provided, however,
that a Holder with an aggregate principal amount in excess of $2,000,000 will
be paid by wire transfer in immediately available funds at the election of such
Holder if such Holder has provided wire transfer instructions to the Company at
least 10 Business Days prior to the payment date.  The Company may mail a check for interest to
the Holder’s registered address. 
Notwithstanding the foregoing, so long as this Security is registered in
the name of a Depositary or its nominee, all payments hereon shall be made by
wire transfer of immediately available funds to the account of the Depositary
or its nominee.

3.                                       PAYING
AGENT, REGISTRAR AND CONVERSION AGENT

Initially, The Bank of New York (the “Trustee”, which
term shall include any successor trustee under the Indenture hereinafter
referred to) will act as Paying Agent, Registrar and Conversion Agent.  The Company may change any Paying Agent,
Registrar or Conversion Agent without notice to the Holder.  The Company or any of its Subsidiaries may,
subject to certain limitations set forth in the Indenture, act as Paying Agent
or Registrar.

 A-5
 

 

 

4.                                       INDENTURE,
LIMITATIONS

This Security is one of a duly authorized issue of
Securities of the Company designated as its 0.50% Convertible Senior Notes due
October 15, 2011 (the “Securities”), issued under an Indenture, dated as of
October 30, 2006 (together with any supplemental indentures thereto, the “Indenture”),
between the Company and the Trustee.  The
terms of this Security include those stated in the Indenture and those required
by or made part of the Indenture by reference to the Trust Indenture Act of
1939, as amended, as in effect on the date of the Indenture.  This Security is subject to all such terms,
and the Holder of this Security is referred to the Indenture and said Act for a
statement of them.

The Securities are senior unsecured obligations of the
Company.  The Indenture does not limit
other debt of the Company, secured or unsecured.

5.                                       PURCHASE
OF SECURITIES AT OPTION OF HOLDER UPON A FUNDAMENTAL CHANGE

At the option of the Holder and subject to the terms
and conditions of the Indenture, the Company shall become obligated to purchase
all or any part specified by the Holder (so long as the principal amount of
such part is $1,000 or an integral multiple of $1,000 in excess thereof) of the
Securities held by such Holder on the date that is 30 Business Days after the
occurrence of a Fundamental Change, at a purchase price equal to 100% of the
principal amount thereof, together with any accrued and unpaid interest up to,
but excluding, the Fundamental Change Purchase Date, payable in cash.  The Holder shall have the right to withdraw
any Fundamental Change Purchase Notice (in whole or in a portion thereof that
is $1,000 or an integral multiple of $1,000 in excess thereof) at any time
prior to 5:00 p.m., New York City time, on the second Trading Day next
preceding the Fundamental Change Purchase Date by delivering a written notice
of withdrawal to the Paying Agent in accordance with the terms of the Indenture.

6.                                       CONVERSION

A Holder of a Security may convert the principal
amount of such Security (or any portion thereof equal to $1,000 or any integral
multiple of $1,000 in excess thereof) into Cash and Common Stock at any time
prior to the close of business on July 15, 2011, subject to the conditions, if
any, set forth in Section 5.01 of the Indenture; provided, however,
that, if the Security is submitted for purchase upon a Fundamental Change, the
conversion right shall terminate at the close of business on the second Trading
Day immediately preceding the Fundamental Change Purchase Date for such
Security or such earlier date as the Holder presents such Security for purchase
(unless the Company shall default in making the Fundamental Change Purchase
Price payment when due, in which case the conversion right shall terminate at
the close of business on the date such default is cured and such Security is
purchased).

The initial Conversion Price is $75.2257 per share,
and the initial Conversion Rate is 13.2933 shares of Common Stock, in each case
subject to adjustment under certain circumstances as provided in the
Indenture.  No fractional shares will be
issued upon conversion; in lieu thereof, the Company shall deliver a number of
shares of Common Stock equal to the aggregate of the fractional shares
otherwise deliverable for each Trading Day during the 

 A-6
 

 

Conversion Period
(rounding down to the nearest whole number) and shall pay an amount in cash
equal to the remainder multiplied by the Volume Weighted Average Price of the
Common Stock on the last day of the Conversion Period.

To convert a Security, a Holder must (a) complete and
duly sign the conversion notice set forth below and deliver such notice to a
Conversion Agent, (b) surrender the Security to a Conversion Agent, if such
Security is represented by a Global Security, by book-entry transfer through
the facilities of the Depositary in accordance with the Applicable Procedures
or, if such Security is represented by a Certificated Security, by delivery of
such Security at the specified office of the Conversion Agent, (c) furnish
appropriate endorsements and transfer documents if required by a Conversion
Agent and (d) pay any transfer or similar tax, if required.  A Holder may convert a portion of a Security
equal to $1,000 or any integral multiple thereof.

A Security in respect of which a Holder had delivered
a Fundamental Change Purchase Notice exercising the option of such Holder to
require the Company to purchase such Security may be converted only if the Fundamental
Change Purchase Notice is withdrawn in accordance with the terms of the
Indenture.

7.                                       [RESERVED]

8.                                       DENOMINATIONS,
TRANSFER, EXCHANGE

The Securities are in registered form, without
coupons, in denominations of $1,000 and integral multiples of $1,000.  A Holder may transfer or exchange Securities
in accordance with the Indenture.  The
Registrar may require a Holder, among other things, to furnish appropriate
endorsements and transfer documents and to pay any taxes or other governmental
charges that may be imposed in relation thereto by law or permitted by the
Indenture.

9.                                       PERSONS
DEEMED OWNERS

The Holder of a Security may be treated as the owner
of it for all purposes.

10.                                 UNCLAIMED
MONEY

If money for the payment of principal, premium, if
any, or interest, if any, remains unclaimed for two years, the Trustee or
Paying Agent will pay the money back to the Company at its written request,
subject to applicable unclaimed property law. 
After that, Holders entitled to money must look to the Company for payment
as general creditors unless an applicable abandoned property law designates
another person.

11.                                 AMENDMENT,
SUPPLEMENT AND WAIVER

Subject to certain exceptions set forth in the
Indenture, the Securities and the Indenture may be amended or supplemented with
the written consent of the Holders of at least a majority in aggregate
principal amount of the Securities then outstanding, and an existing default or
Event of Default with respect to the Securities and its consequence or
compliance with any provision of the Securities or the Indenture may be waived
in a particular instance with the consent of the Holders of a majority in
aggregate principal amount of the Securities then outstanding.  Without

 A-7
 

 

notice to or the consent
of any Holder, the Company and the Trustee may amend or supplement the
Indenture or the Securities to, among other things, cure any ambiguity, correct
any defect or inconsistency or make any other change that does not adversely
affect the rights of any Holder.

12.                                 SUCCESSOR
ENTITY

When a successor corporation assumes all the
obligations of its predecessor under the Securities and the Indenture in
accordance with the terms and conditions of the Indenture, the predecessor
corporation (except in certain circumstances specified in the Indenture) shall
be released from those obligations.

13.                                 DEFAULTS
AND REMEDIES

Under the Indenture, an Event of Default with respect
to the Securities includes: (i) default for 30 days in payment of any interest
on any Securities; (ii) default in payment of any principal of (including,
without limitation, any premium, if any, on) the Securities when due; (iii)
defaults in the payment of Cash and shares of Common Stock (if any) upon
conversion of any Security (including any Additional Shares), when the same
becomes due and payable; (iv) failure by the Company for 60 days after notice
to it to comply with any of its other agreements contained in the Securities or
in the Indenture with respect to the Securities (other than in the case of a
failure to file reports as specified in the Indenture); (v) default in payment
of the purchase price of any Security when due and payable; (vi) failure to
provide a Fundamental Change Purchase Notice when required; (vii) any
Indebtedness for money borrowed of the Company or a Significant Subsidiary in
an outstanding principal amount in excess of $20 million is not paid at stated
maturity or upon acceleration and such Indebtedness is not discharged, or such
default in payment or acceleration is not cured or rescinded after the applicable
grace period, if any, specified in the agreement or Instrument relating to such
Indebtedness; (viii) the Company or a Significant Subsidiary fails to pay one
or more final and non-appealable judgments entered by a court of competent
jurisdiction, the aggregate uninsured or unbonded portion of which is in excess
of $20 million, if the judgments are not paid, discharged or stayed within 30
days; and (xi) certain events of bankruptcy, insolvency or reorganization of
the Company or any Significant Subsidiary.  If an Event of Default with respect to the
Securities (other than as a result of certain events of bankruptcy, insolvency
or reorganization specified in the Indenture) occurs and is continuing, the
Trustee or the Holders of at least 25% in aggregate principal amount of the
Securities then outstanding may declare all unpaid principal to the date of
acceleration on the Securities then outstanding to be due and payable
immediately, all as and to the extent provided in the Indenture.  If an Event of Default occurs as a result of
certain events of bankruptcy, insolvency or reorganization specified in the
Indenture, all unpaid principal of the Securities then outstanding shall become
due and payable immediately without any declaration or other act on the part of
the Trustee or any Holder, all as and to the extent provided in the
Indenture.  Holders may not enforce the
Indenture or the Securities except as provided in the Indenture.  The Trustee may require indemnity
satisfactory to it before it enforces the Indenture or the Securities.  Subject to certain limitations, Holders of a
majority in aggregate principal amount of the Securities then outstanding may
direct the Trustee in its exercise of any trust or power.  The Trustee may withhold from Holders notice
of any continuing default (except a default in payment of principal, any
premium, or interest) if it determines that withholding notice 

 A-8
 

 

is in their
interests.  The Company is required to
file periodic reports with the Trustee as to the absence of default.

14.                                 TRUSTEE
DEALINGS WITH THE COMPANY

The Bank of New York, the Trustee under the Indenture,
in its individual or any other capacity, may make loans to, accept deposits
from and perform services for the Company or an Affiliate of the Company and
may otherwise deal with the Company or an Affiliate of the Company, as if it
were not the Trustee.

15.                                 NO
RECOURSE AGAINST OTHERS

A director, officer, employee or shareholder, as such,
of the Company shall not have any liability for any obligations of the Company
under the Securities or the Indenture or for any claim based on, in respect of
or by reason of such obligations or their creation.  The Holder of this Security by accepting this
Security waives and releases all such liability.  The waiver and release are part of the
consideration for the issuance of this Security.

16.                                 AUTHENTICATION

This Security shall not be valid until the Trustee or
an authenticating agent manually or by facsimile signs the certificate of
authentication on the other side of this Security.

17.                                 ABBREVIATIONS
AND DEFINITIONS

Customary abbreviations may be used in the name of the
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 UGMA (= Uniform Gifts to
Minors Act).

All terms defined in the Indenture and used in this
Security but not specifically defined herein are used herein as so defined.

18.                                 INDENTURE
TO CONTROL; GOVERNING LAW

In the case of any conflict between the provisions of
this Security and the Indenture, the provisions of the Indenture shall
control.  This Security shall be governed
by, and construed in accordance with, the laws of the State of New York without
giving effect to applicable principles of conflicts of law to the extent that
the application of the laws of another jurisdiction would be required thereby.

The Company will furnish to any Holder, upon written
request and without charge, a copy of the Indenture.  Requests may be made to: United Therapeutics
Corporation, 1110 Spring Street, Silver Spring, Maryland 20910, Attention:
Chief Financial Officer.

 A-9

 

ASSIGNMENT FORM

To assign this Security, fill in the form below:

I or we assign and transfer this Security to

	
  

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

  
	
   

  
	
   

  
	
   

  
	
   

  
	
   

  
	
   

  
	
   

  
	
   

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

  
	
   

  
	
  and irrevocably appoint

  
	
   

  
	
   

  
	
  agent to
  transfer this Security on the books of the Company. The agent may substitute
  another to act for him or her.

  

 

	
  

  	
   

  	
  Your Signature:

  
	
   

  	
   

  	
   

  
	
  Date:

  	
   

  	
   

  	
   

  
	
   

  	
   

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

  
				

 

	
  

  	
  *Signature guaranteed by:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  	
   

  

*              The
signature must be guaranteed by an institution which is a member of one of the
following recognized signature guaranty programs: (i) the Securities Transfer
Agent Medallion Program (STAMP); (ii) the New York Stock Exchange Medallion
Program (MSP); (iii) the Stock Exchange Medallion Program (SEMP); or (iv) such
other guaranty program acceptable to the Trustee.

 A-10
 

 

 

CONVERSION NOTICE

To convert this Security into Common Stock of the
Company, check the box:   o

To convert only part of this Security, state the
principal amount to be converted (must be $1,000 or a integral multiple of
$1,000): 
$            .

If you want the stock certificate made out in another
person’s name, fill in the form below:

	
  

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

  
	
   

  
	
   

  
	
   

  
	
   

  
	
   

  
	
   

  
	
   

  
	
   

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

  
	
   

  

 

	
  

  	
   

  	
  Your Signature:

  
	
   

  	
   

  	
   

  
	
  Date:

  	
   

  	
   

  	
   

  
	
   

  	
   

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

  
				

 

	
  

  	
  *Signature guaranteed by:

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  By:

  	
   

  	
   

  	
   

  

*              The
signature must be guaranteed by an institution which is a member of one of the
following recognized signature guaranty programs: (i) the Securities Transfer
Agent Medallion Program (STAMP); (ii) the New York Stock Exchange Medallion
Program (MSP); (iii) the Stock Exchange Medallion Program (SEMP); or (iv) such
other guaranty program acceptable to the Trustee.

 

 A-11
 

 

 

OPTION TO ELECT REPURCHASE

UPON A FUNDAMENTAL CHANGE

To:  United
Therapeutics Corporation

The undersigned
registered owner of this Security hereby irrevocably acknowledges receipt of a
notice from United Therapeutics Corporation (the “Company”) as to the
occurrence of a Fundamental Change with respect to the Company and requests and
instructs the Company to redeem the entire principal amount of this Security,
or the portion thereof (which is $1,000 or an integral multiple thereof) below
designated, in accordance with the terms of the Indenture referred to in this
Security at a purchase price equal to the Fundamental Change Purchase Price,
payable in Cash.

	
  Dated:

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
  Signature(s) must be guaranteed by a qualified
  guarantor institution with membership in an approved signature guarantee
  program pursuant to Rule 17Ad-15 under the Securities Exchange Act of
  1934.

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
   

  	
   

  	
  Signature Guaranty

  
	
   

  	
   

  	
   

  
	
  Principal amount to be redeemed (in an integral
  multiple of $1,000, if less than all):

  	
   

  	
   

  
	
   

  	
   

  	
   

  
	
  NOTICE: The signature to the foregoing Election must
  correspond to the Name as written upon the face of this Security in every
  particular, without alteration or any change whatsoever.

  

 

 A-12
 

 

 

SCHEDULE
OF EXCHANGES OF SECURITIES (4)

The following exchanges,
redemptions, repurchases or conversions of a part of this global Security have
been made:

	
  

  Principal Amount

  of this Global Security

  Following Such

  Decrease

  Date of Exchange

  (or Increase)

  	
   

  	
  

  Authorized

  Signatory of

  Securities

  Custodian

  	
   

  	
  

  

  Amount of Decrease in

  Principal Amount

  of this Global Security

  	
   

  	
  

  Amount of

  Increase in

  Principal Amount

  of this Global Security

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  

(4)             This
phrase should be included only if the Security is a Global Security.

 

 A-13

 

EXHIBIT
B

FORM OF TRANSFER CERTIFICATE FOR TRANSFER

OF RESTRICTED COMMON STOCK

[NAME AND ADDRESS OF COMMON STOCK TRANSFER
AGENT]

Re:                               United
Therapeutics Corporation 0.50% Convertible Senior Notes Due October 15, 2011
(the “Securities”)

Reference is hereby made
to the Indenture dated as of October 30, 2006 between the Company and the
Trustee (collectively, the “Indenture”). 
Capitalized terms used but not defined herein shall have the meanings
given them in the Indenture.

This letter relates to
_________ shares of Common Stock [that are to be] [represented by the accompanying
certificate(s) that were] issued upon conversion of Securities and which are
held in the name of [name of transferor] (the “Transferor”) to effect the
transfer of such Common Stock.

In connection with the
transfer of such shares of Common Stock, the undersigned confirms that such
shares of Common Stock are being transferred:

CHECK ONE BOX BELOW:

o            To
the Company or any Subsidiary thereof.

o            To
a person the undersigned reasonably believes is a “qualified institutional
buyer” (as defined in Rule 144A under the Securities Act of 1933, as amended
(the “Securities Act”)), in accordance with Rule 144A under the Securities Act.

o            Pursuant
to another available exemption from the registration requirements of the
Securities Act

 B-1
 

 

 

Unless one of the boxes
is checked, the transfer agent will refuse to register any of the Common Stock
evidenced by this certificate in the name of any person other than the registered
holder thereof; provided, however,
that if the third box is checked, the transfer agent may require, prior to
registering any such transfer of the Common Stock such certifications and other
information, including opinions of counsel, as the Company has reasonably
requested in writing, by delivery to the transfer agent of a standing letter of
instruction, to confirm that such transfer is being made pursuant to an
exemption from, or in a transaction not subject to, the registration requirements
of the Securities Act.

[Name of Transferor],

	
  

  	
  By:

  	
   

  
	
   

  	
   

  	
  Name:

  
	
   

  	
   

  	
  Title:

  
	
   

  	
  Dated:

  	
   

  

 

 B-2

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00111-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00111-of-00352.parquet"}]]