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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, par value $.01 per share and associated preferred
stock purchase rights
--------------------------------------------------------------------------------
(Title of Class of Securities)
91307C102
-------------------------------------------------------
(CUSIP Number)
February 22, 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 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 the purpose 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).
----------------------------- -----------------------
CUSIP NO. 91307C102 13G PAGE 2 OF 10 PAGES
----------------------------- -----------------------
--------- ----------------------------------------------------------------------
1 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES
ONLY) Ziff Asset Management, L.P.
--------- ----------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE
INSTRUCTIONS) (A) |_|
(B) |_|
--------- ----------------------------------------------------------------------
3 SEC USE ONLY
--------- ----------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
--------- ----------------------------------------------------------------------
5 SOLE VOTING POWER
NUMBER OF 0
SHARES
------ -------------------------------------------------
6 SHARED VOTING POWER
BENEFICIALLY
1,475,939
OWNED BY
------ -------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
0
REPORTING
------ -------------------------------------------------
PERSON 8 SHARED DISPOSITIVE POWER
WITH
1,475,939
--------- ----------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,475,939
--------- ----------------------------------------------------------------------
10 CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
(SEE INSTRUCTIONS) |_|
--------- ----------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
6.4%
--------- ----------------------------------------------------------------------
12 TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
PN
--------- ----------------------------------------------------------------------
----------------------------- -----------------------
CUSIP NO. 91307C102 13G PAGE 3 OF 10 PAGES
----------------------------- -----------------------
--------- ----------------------------------------------------------------------
1 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES
ONLY) PBK Holdings, Inc.
--------- ----------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE
INSTRUCTIONS) (A) |_|
(B) |_|
--------- ----------------------------------------------------------------------
3 SEC USE ONLY
--------- ----------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
--------- ----------------------------------------------------------------------
5 SOLE VOTING POWER
NUMBER OF 0
SHARES
------ -------------------------------------------------
6 SHARED VOTING POWER
BENEFICIALLY
1,475,939
OWNED BY
------ -------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
0
REPORTING
------ -------------------------------------------------
PERSON 8 SHARED DISPOSITIVE POWER
WITH
1,475,939
--------- ----------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,475,939
--------- ----------------------------------------------------------------------
10 CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
(SEE INSTRUCTIONS) |_|
--------- ----------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
6.4%
--------- ----------------------------------------------------------------------
12 TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
CO
--------- ----------------------------------------------------------------------
----------------------------- -----------------------
CUSIP NO. 91307C102 13G PAGE 4 OF 10 PAGES
----------------------------- -----------------------
--------- ----------------------------------------------------------------------
1 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES
ONLY) Philip B. Korsant
--------- ----------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE
INSTRUCTIONS) (A) |_|
(B) |_|
--------- ----------------------------------------------------------------------
3 SEC USE ONLY
--------- ----------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
United States of America
--------- ----------------------------------------------------------------------
5 SOLE VOTING POWER
NUMBER OF 0
SHARES
------ -------------------------------------------------
6 SHARED VOTING POWER
BENEFICIALLY
1,475,939
OWNED BY
------ -------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
0
REPORTING
------ -------------------------------------------------
PERSON 8 SHARED DISPOSITIVE POWER
WITH
1,475,939
--------- ----------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,475,939
--------- ----------------------------------------------------------------------
10 CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
(SEE INSTRUCTIONS) |_|
--------- ----------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
6.4%
--------- ----------------------------------------------------------------------
12 TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
IN
--------- ----------------------------------------------------------------------
----------------------------- -----------------------
CUSIP NO. 91307C102 13G PAGE 5 OF 10 PAGES
----------------------------- -----------------------
--------- ----------------------------------------------------------------------
1 NAMES OF REPORTING PERSONS
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES
ONLY) ZBI Equities, L.L.C.
--------- ----------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE
INSTRUCTIONS) (A) |_|
(B) |_|
--------- ----------------------------------------------------------------------
3 SEC USE ONLY
--------- ----------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
--------- ----------------------------------------------------------------------
5 SOLE VOTING POWER
NUMBER OF 0
SHARES
------ -------------------------------------------------
6 SHARED VOTING POWER
BENEFICIALLY
1,475,939
OWNED BY
------ -------------------------------------------------
EACH 7 SOLE DISPOSITIVE POWER
0
REPORTING
------ -------------------------------------------------
PERSON 8 SHARED DISPOSITIVE POWER
WITH
1,475,939
--------- ----------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,475,939
--------- ----------------------------------------------------------------------
10 CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
(SEE INSTRUCTIONS) |_|
--------- ----------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
6.4%
--------- ----------------------------------------------------------------------
12 TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
IA
--------- ----------------------------------------------------------------------
ITEM 1. (a) NAME OF ISSUER
United Therapeutics Corporation
ITEM 1. (b) ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES
1110 Spring Street
Silver Spring, MD 20910
ITEM 2. (a) NAME OF PERSON FILING
This Schedule 13G is being filed on behalf of the following persons (the
"Reporting Persons")*:
(i) Ziff Asset Management, L.P. ("ZAM");
(ii) PBK Holdings, Inc. ("PBK");
(iii) Philip B. Korsant; and
(iv) ZBI Equities, L.L.C. ("ZBI").
* Attached as Exhibit A is a copy of an agreement among the Reporting
Persons that this Schedule 13G is being filed on behalf of each of them.
ITEM 2. (b) ADDRESS OF PRINCIPAL BUSINESS OFFICE OR, IF NONE, RESIDENCE
Ziff Asset Management, L.P.
283 Greenwich Avenue
Greenwich, CT 06830
PBK Holdings, Inc.
283 Greenwich Avenue
Greenwich, CT 06830
Philip B. Korsant
283 Greenwich Avenue
Greenwich, CT 06830
ZBI Equities, L.L.C.
283 Greenwich Avenue
Greenwich, CT 06830
ITEM 2. (c) CITIZENSHIP
See Item 4 of the attached cover pages.
ITEM 2. (d) TITLE OF CLASS OF SECURITIES
Common Stock, par value $.01 per share and associated preferred stock
purchase rights (the "Common Stock")
ITEM 2. (e) CUSIP NUMBER
91307C102
ITEM 3.
Not applicable as this Schedule 13G is filed pursuant to Rule 13d-1(c).
ITEM 4. OWNERSHIP
(a) Amount beneficially owned:
See Item 9 of the attached cover pages.
(b) Percent of class:
See Item 11 of the attached cover pages.
(c) Number of shares as to which such person has:
(i) Sole power to vote or to direct the vote:
See Item 5 of the attached cover pages.
(ii) Shared power to vote or to direct the vote:
See Item 6 of the attached cover pages.
(iii) Sole power to dispose or to direct the disposition:
See Item 7 of the attached cover pages.
(iv) Shared power to dispose or to direct the disposition:
See Item 8 of the attached cover pages.
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
Not Applicable.
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON
ZAM is the owner of record of the shares of Common Stock reported herein.
Each of PBK, Philip B. Korsant, and ZBI may be deemed to beneficially own
the Common Stock reported herein as a result of the direct or indirect
power to vote or dispose of such stock.
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
Not Applicable.
ITEM 9. NOTICE OF DISSOLUTION OF GROUP
Not Applicable.
ITEM 10. CERTIFICATION
By signing below I certify that, to the best of my 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.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and
belief, I certify that the information set forth in this statement is true,
complete and correct.
Dated: March 2, 2006
ZIFF ASSET MANAGEMENT, L.P.
By: PBK Holdings, Inc., its general partner
By: /s/ DAVID GRAY
---------------------------------------
Name: David Gray
Title: Vice President
PBK HOLDINGS, INC.
By: /s/ DAVID GRAY
---------------------------------------
Name: David Gray
Title: Vice President
/s/ PHILIP B. KORSANT
-------------------------------------
Philip B. Korsant
ZBI EQUITIES, L.L.C.
By: PBK Holdings, Inc., its sole member
By: /s/ DAVID GRAY
---------------------------------------
Name: David Gray
Title: Vice President
EXHIBIT A
The undersigned, Ziff Asset Management, L.P., a Delaware limited
partnership, PBK Holdings, Inc., a Delaware corporation, Philip B. Korsant,
and ZBI Equities, L.L.C., a Delaware limited liability company, hereby
agree and acknowledge that the information required by this Schedule 13G,
to which this Agreement is attached as an exhibit, is filed on behalf of
each of them. The undersigned further agree that any further amendments or
supplements thereto shall also be filed on behalf of each of them.
Dated: March 2, 2006
ZIFF ASSET MANAGEMENT, L.P.
By: PBK Holdings, Inc., its general partner
By: /s/ DAVID GRAY
---------------------------------------
Name: David Gray
Title: Vice President
PBK HOLDINGS, INC.
By: /s/ DAVID GRAY
---------------------------------------
Name: David Gray
Title: Vice President
/s/ PHILIP B. KORSANT
-------------------------------------
Philip B. Korsant
ZBI EQUITIES, L.L.C.
By: PBK Holdings, Inc., its sole member
By: /s/ DAVID GRAY
---------------------------------------
Name: David Gray
Title: Vice President