CUSIP No. 91307C102                   13G                  Page 1 of 11 Pages

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                             ----------------------

                                  SCHEDULE 13G

                    Under the Securities Exchange Act of 1934

                         United Therapeutics Corporation
                                (Name of Issuer)

                     Common Stock, $0.01 par value per share
                         (Title of Class of Securities)

                                    91307C102
                                 (CUSIP Number)

                                December 1, 2006
             (Date of Event Which Requires Filing of this statement)


     Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:
     [ ]  Rule 13d-1(b)
     [X]  Rule 13d-1(c)
     [ ]  Rule 13d-1(d)


----------------
     *The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which would
alter the disclosures provided in a prior cover page.

     The information required in the remainder of this cover page shall not be
deemed to be "filed" for purposes of Section 18 of the Securities Exchange Act
of 1934 ("Act") or otherwise subject to the liabilities of that section of the
Act but shall be subject to all other provisions of the Act (however, see the
Notes).

                               Page 1 of 12 Pages




CUSIP No. 91307C102                   13G                  Page 2 of 11 Pages

----------------------------------------------------------------------
     (1)    NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            GLG Partners LP
-----------------------------------------------------------------------
     (2)    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
                                                               (a)  [X]
                                                               (b)  [ ]
-----------------------------------------------------------------------
     (3)    SEC USE ONLY
-----------------------------------------------------------------------
     (4)    CITIZENSHIP OR PLACE OF ORGANIZATION

            United Kingdom
-----------------------------------------------------------------------
NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         --------------------------------------------------------

BENEFICIALLY   (6)  SHARED VOTING POWER
                    1,436,962 Shares

OWNED BY       --------------------------------------------------------

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      --------------------------------------------------------

PERSON WITH:  (8)   SHARED DISPOSITIVE POWER
                    1,436,962 Shares

-----------------------------------------------------------------------
     (9)    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
                    1,436,962 Shares

-----------------------------------------------------------------------
     (10)   CHECK BOX IF THE AGGREGATE AMOUNT
            IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
                                                                           [ ]
-----------------------------------------------------------------------
     (11)   PERCENT OF CLASS REPRESENTED
            BY AMOUNT IN ROW (9)
            6.2%
-----------------------------------------------------------------------
     (12)   TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
            PN
-----------------------------------------------------------------------



CUSIP No. 91307C102                   13G                  Page 3 of 11 Pages

-----------------------------------------------------------------------
     (1)    NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            GLG Partners Limited
-----------------------------------------------------------------------
     (2)    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
                                                               (a)  [X]
                                                               (b)  [ ]
-----------------------------------------------------------------------
     (3)    SEC USE ONLY
-----------------------------------------------------------------------
     (4)    CITIZENSHIP OR PLACE OF ORGANIZATION

            United Kingdom
-----------------------------------------------------------------------
NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         --------------------------------------------------------

BENEFICIALLY   (6)  SHARED VOTING POWER
                        1,436,962 Shares
OWNED BY       --------------------------------------------------------

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      --------------------------------------------------------

PERSON WITH:   (8)  SHARED DISPOSITIVE POWER
                        1,436,962 Shares
-----------------------------------------------------------------------
     (9)    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            1,436,962 Shares
-----------------------------------------------------------------------
     (10)   CHECK BOX IF THE AGGREGATE AMOUNT
            IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
                                                                           [ ]
-----------------------------------------------------------------------
     (11)   PERCENT OF CLASS REPRESENTED
            BY AMOUNT IN ROW (9)
             6.2%
-----------------------------------------------------------------------
     (12)   TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
            IA, HC
-----------------------------------------------------------------------



CUSIP No. 91307C102                   13G                  Page 4 of 11 Pages

-----------------------------------------------------------------------
     (1)    NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Noam Gottesman
-----------------------------------------------------------------------
     (2)    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
                                                               (a)  [X]
                                                               (b)  [ ]
-----------------------------------------------------------------------
     (3)    SEC USE ONLY
-----------------------------------------------------------------------
     (4)    CITIZENSHIP OR PLACE OF ORGANIZATION

            United States
-----------------------------------------------------------------------
NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         --------------------------------------------------------

BENEFICIALLY   (6)  SHARED VOTING POWER
                    1,436,962 Shares
OWNED BY       --------------------------------------------------------

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      --------------------------------------------------------

PERSON WITH:   (8)  SHARED DISPOSITIVE POWER
                    1,436,962 Shares
-----------------------------------------------------------------------
     (9)    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            1,436,962 Shares
-----------------------------------------------------------------------
     (10)   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN
            SHARES (SEE INSTRUCTIONS)
                                                                           [ ]
-----------------------------------------------------------------------
     (11)   PERCENT OF CLASS REPRESENTED
            BY AMOUNT IN ROW (9)
            6.2%
-----------------------------------------------------------------------
     (12)   TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
            IN, HC
-----------------------------------------------------------------------




CUSIP No. 91307C102                   13G                  Page 5 of 11 Pages

-----------------------------------------------------------------------
     (1)    NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Pierre Lagrange
-----------------------------------------------------------------------
     (2)    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
                                                               (a)  [X]
                                                               (b)  [ ]
-----------------------------------------------------------------------
     (3)    SEC USE ONLY
-----------------------------------------------------------------------
     (4)    CITIZENSHIP OR PLACE OF ORGANIZATION

            Belgium
-----------------------------------------------------------------------
NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         --------------------------------------------------------

BENEFICIALLY   (6)  SHARED VOTING POWER
                    1,436,962 Shares
OWNED BY       --------------------------------------------------------

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      --------------------------------------------------------

PERSON WITH:   (8)  SHARED DISPOSITIVE POWER
                    1,436,962 Shares
-----------------------------------------------------------------------
     (9)    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            1,436,962 Shares
-----------------------------------------------------------------------
     (10)   CHECK BOX IF THE AGGREGATE AMOUNT
            IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
                                                                           [ ]
-----------------------------------------------------------------------
     (11)   PERCENT OF CLASS REPRESENTED
            BY AMOUNT IN ROW (9)
             6.2%
-----------------------------------------------------------------------
    (12)    TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
            IN, HC
-----------------------------------------------------------------------




CUSIP No. 91307C102                   13G                  Page 6 of 11 Pages

     (1)    NAMES OF REPORTING PERSONS
            I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)

            Emmanuel Roman
-----------------------------------------------------------------------
     (2)    CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
                                                               (a)  [X]
                                                               (b)  [ ]
-----------------------------------------------------------------------
     (3)    SEC USE ONLY
-----------------------------------------------------------------------
     (4)    CITIZENSHIP OR PLACE OF ORGANIZATION

            France
-----------------------------------------------------------------------
NUMBER OF      (5)  SOLE VOTING POWER
                    0
SHARES         --------------------------------------------------------

BENEFICIALLY   (6)  SHARED VOTING POWER
                    1,436,962 Shares
OWNED BY       --------------------------------------------------------

EACH           (7)  SOLE DISPOSITIVE POWER
                    0
REPORTING      --------------------------------------------------------

PERSON WITH:   (8)  SHARED DISPOSITIVE POWER
                    1,436,962 Shares
-----------------------------------------------------------------------
     (9)    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            1,436,962 Shares
-----------------------------------------------------------------------
     (10)   CHECK BOX IF THE AGGREGATE AMOUNT
            IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
                                                                           [ ]
-----------------------------------------------------------------------
     (11)   PERCENT OF CLASS REPRESENTED
            BY AMOUNT IN ROW (9)
            6.2%
-----------------------------------------------------------------------
     (12)   TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
            IN, HC
-----------------------------------------------------------------------




CUSIP No. 91307C102                   13G                  Page 7 of 11 Pages

Item 1.

(a)  Name of Issuer

            United Therapeutics Corporation, a Delaware corporation (the
            "Company").

(b)  Address of Issuer's Principal Executive Offices

            1110 Spring Street
            Silver Spring, MD 20910

Item 2(a).  Name of Person Filing

         This statement is filed by the entities and persons listed below, who
         are collectively referred to herein as "Reporting Persons," with
         respect to Shares (as defined in Item 2(d) below) of the Company:

         INVESTMENT MANAGER

         (i)      GLG Partners, LP (the "Investment Manager"), with respect to
                  the Shares held by certain funds to which the Investment
                  Manager serves as investment manager (collectively, the "GLG
                  Funds").

         GENERAL PARTNER

         (ii)     GLG Partners Limited (the "General Partner"), which serves as
                  the general partner of the Investment Manager, with respect to
                  the Shares held by each of the GLG Funds.

         REPORTING INDIVIDUALS

         (iii)    Mr. Noam Gottesman ("Mr. Gottesman"), with respect to the
                  Shares held by each of the GLG Funds.

         (iv)     Mr. Pierre Lagrange ("Mr. Lagrange"), with respect to the
                  Shares held by each of the GLG Funds.

         (v)      Mr. Emmanuel Roman ("Mr. Roman"), with respect to the Shares
                  held by each of the GLG Funds.

         Mr. Gottesman, Mr. Lagrange and Mr. Roman are collectively referred to
as the "Reporting Individuals."

         The Investment Manager serves as the investment manager to each of the
         GLG Funds. The General Partner serves as the general partner to the
         Investment Manager. Each of the Reporting Individuals is a Managing
         Director of the General Partner.

Item 2(b).  Address of Principal Business Office or, if none, Residence

         The address of the principal business office of each of the Reporting
Persons is:

         c/o GLG Partners LP
         1 Curzon Street
         London W1J 5HB
         United Kingdom




CUSIP No. 91307C102                   13G                  Page 8 of 11 Pages

Item 2(c).  Citizenship

         Citizenship is set forth in Row 4 of the cover page for each Reporting
         Person hereto and is incorporated herein by reference for each such
         Reporting Person.

Item 2(d)  Title of Class of Securities

            Common Stock, $0.01 par value per share (the "Shares")

Item 2(e)  CUSIP Number

            91307C102

Item 3. If this statement is filed pursuant to ss.ss.240.13d-1(b) or
240.13d-2(b) or (c), check whether the person filing is a:

(a) [ ] Broker or dealer registered under Section 15 of the Act (15 U.S.C. 78o).

(b) [ ] Bank as defined in Section 3(a)(6) of the Act (15 U.S.C. 78c).

(c) [ ] Insurance company as defined in Section 3(a)(19) of the Act (15
        U.S.C. 78c).

(d) [ ] Investment company registered under Section 8 of the Investment
        Company Act of 1940 (15 U.S.C. 80a-8).

(e) [ ] An investment adviser in accordance with ss.240.13d-1(b)(1)(ii)(E);

(f) [ ] An employee benefit plan or endowment fund in accordance with
        ss.240.13d-1(b)(1)(ii)(F);

(g) [ ] A parent holding company or control person in accordance with
        ss.240.13d-1(b)(1)(ii)(G);

(h) [ ] A savings association as defined in Section 3(b) of the Federal
        Deposit Insurance Act (12 U.S.C. 1813);

(i) [ ] A church plan that is excluded from the definition of an investment
        company under Section 3(c)(14) of the Investment Company Act of 1940 (15
        U.S.C. 80a-3);

(j) [ ] Group, in accordance with Rule 13d-1(b)(1)(ii)(J).

Item 4.   Ownership

            Provide the following information regarding the aggregate number and
percentage of the class of securities of the issuer identified in Item 1.

         The information required by Items 4(a) - (c) is set forth in Rows 5 -
         11 of the cover page for each Reporting Person hereto and is
         incorporated herein by reference for each such Reporting Person. The
         Company's most recent current report on Form 10-Q that was filed on
         November 2, 2006, indicates there were 23,216,212 Shares outstanding as
         of October 27, 2006.

         The Investment Manager, which serves as the investment manager to each
         of the GLG Funds, may be deemed to be the beneficial owner of all
         Shares owned by the GLG Funds. The General Partner, as general partner
         to the




CUSIP No. 91307C102                   13G                  Page 9 of 11 Pages

         Investment Manager, may be deemed to be the beneficial owner of
         all Shares owned by the GLG Funds. Each of the Reporting Individuals,
         as a Managing Director of the General Partner with the power to
         exercise investment discretion, may be deemed to be the beneficial
         owner of all Shares owned by the GLG Funds. Each of the Investment
         Manager, the General Partner, and the Reporting Individuals hereby
         disclaims any beneficial ownership of any such Shares, except for their
         pecuniary interest therein.

Item 5.  Ownership of Five Percent or Less of a Class

            If this statement is being filed to report the fact that as of the
date hereof the reporting person has ceased to be the beneficial owner of more
than five percent of the class of securities, check the following: [ ]

Item 6.  Ownership of More than Five Percent on Behalf of Another Person

            Not applicable.

Item  7.   Identification and Classification of the Subsidiary Which Acquired
           the Security Being Reported on by the Parent Holding Company

            Not applicable.

Item 8.  Identification and Classification of Members of the Group

         See Exhibit I.

Item 9.  Notice of Dissolution of Group

            Not applicable.

Item 10. Certification

            By signing below each of the undersigned certifies that, to the best
of its knowledge and belief, the securities referred to above were not acquired
and are not held for the purpose of or with the effect of changing or
influencing the control of the issuer of the securities and were not acquired
and are not held in connection with or as a participant in any transaction
having that purpose or effect.

Exhibits:

Exhibit I: Joint Filing Agreement, dated as of December 15, 2006, by and among
GLG Partners LP, GLG Partners Limited, Noam Gottesman, Pierre Lagrange and
Emmanuel Roman.



CUSIP No. 91307C102                   13G                  Page 10 of 11 Pages


                                   SIGNATURES

            After reasonable inquiry and to the best of its knowledge and
belief, each of the undersigned certifies that the information with respect to
it set forth in this statement is true, complete, and correct.

Dated: December 15, 2006


GLG PARTNERS LIMITED                        GLG PARTNERS LP
                                            By: GLG Partners Limited,
                                            as its General Partner
/s/ Emmanuel Roman
-----------------------------------
Name: Emmanuel Roman
Title: Attorney-in-Fact for
Noam Gottesman, Managing Director           /s/ Emmanuel Roman
                                            -----------------------------------
                                            Name: Emmanuel Roman
                                            Title: Attorney-in-Fact for
/s/ Victoria Parry                          Noam Gottesman, Managing Director
-----------------------------------
Name: Victoria Parry
Title: Senior Legal Counsel
                                             /s/ Victoria Parry
                                            -----------------------------------
                                            Name: Victoria Parry
                                            Title: Senior Legal Counsel


/s/ Emmanuel Roman
-----------------------------------
Emmanuel Roman, individually and
on behalf of Noam Gottesman and
Pierre Lagrange

The Powers of Attorney executed by Noam Gottesman and Pierre Lagrange,
authorizing Emmanuel Roman to sign and file this Schedule 13G on each person's
behalf, which were filed with the Schedule 13G filed with the Securities and
Exchange Commission on December 15, 2006 by such Reporting Persons with respect
to the common stock of Movado Group, Inc., are hereby incorporated by reference.




CUSIP No. 91307C102                   13G                  Page 11 of 11 Pages

                                    EXHIBIT I

                             JOINT FILING AGREEMENT

This will confirm the agreement by and among the undersigned that the Schedule
13G filed with the Securities and Exchange Commission on or about the date
hereof with respect to the beneficial ownership by the undersigned of the Shares
is being filed, and all amendments thereto will be filed, on behalf of each of
the persons and entities named below in accordance with Rule 13d-1(k) under the
Securities Exchange Act of 1934, as amended. This Agreement may be executed in
two or more counterparts, each of which shall be deemed an original, but all of
which together shall constitute one and the same instrument.

Dated as of December 15, 2006


GLG PARTNERS LIMITED                        GLG PARTNERS LP
                                            By: GLG Partners Limited,
                                            as its General Partner
/s/ Emmanuel Roman
-----------------------------------
Name: Emmanuel Roman
Title: Attorney-in-Fact for
Noam Gottesman, Managing Director           /s/ Emmanuel Roman
                                            -----------------------------------
                                            Name: Emmanuel Roman
                                            Title: Attorney-in-Fact for
/s/ Victoria Parry                          Noam Gottesman, Managing Director
-----------------------------------
Name: Victoria Parry
Title: Senior Legal Counsel
                                             /s/ Victoria Parry
                                             -----------------------------------
                                            Name: Victoria Parry
                                            Title: Senior Legal Counsel


/s/ Emmanuel Roman
-----------------------------------
Emmanuel Roman, individually and
on behalf of Noam Gottesman and
Pierre Lagrange