UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G UNDER THE SECURITIES EXCHANGE ACT OF 1934 (AMENDMENT NO. 1)* UNITED THERAPEUTICS CORPORATION -------------------------------------------------------------------------------- (Name of Issuer) Common Stock, $0.01 Par Value Per Share -------------------------------------------------------------------------------- (Title of Class of Securities) 91307C102 (CUSIP Number) December 31, 2004 (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 on 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). Page 1 of 12 CUSIP No. 91307C102 13G Page 2 of 12 Pages ________________________________________________________________________________ 1. NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) S.A.C. Capital Advisors, LLC ________________________________________________________________________________ 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [X] ________________________________________________________________________________ 3. SEC USE ONLY ________________________________________________________________________________ 4. CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ________________________________________________________________________________ NUMBER OF 5. SOLE VOTING POWER SHARES 0 _________________________________________________________________ BENEFICIALLY 6. SHARED VOTING POWER OWNED BY 400,000 (see Item 4) _________________________________________________________________ EACH 7. SOLE DISPOSITIVE POWER REPORTING 0 _________________________________________________________________ PERSON 8. SHARED DISPOSITIVE POWER WITH 400,000 (see Item 4) ________________________________________________________________________________ 9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 400,000 (see Item 4) ________________________________________________________________________________ 10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 1.8% (see Item 4) ________________________________________________________________________________ 12. TYPE OF REPORTING PERSON* 00 ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 2 of 12 CUSIP No. 91307C102 13G Page 3 of 12 Pages ________________________________________________________________________________ 1. NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) S.A.C. Capital Management, LLC ________________________________________________________________________________ 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [X] ________________________________________________________________________________ 3. SEC USE ONLY ________________________________________________________________________________ 4. CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ________________________________________________________________________________ NUMBER OF 5. SOLE VOTING POWER SHARES 0 _________________________________________________________________ BENEFICIALLY 6. SHARED VOTING POWER OWNED BY 400,000 (see Item 4) _________________________________________________________________ EACH 7. SOLE DISPOSITIVE POWER REPORTING 0 _________________________________________________________________ PERSON 8. SHARED DISPOSITIVE POWER WITH 400,000 (see Item 4) ________________________________________________________________________________ 9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 400,000 (see Item 4) ________________________________________________________________________________ 10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 1.8% (see Item 4) ________________________________________________________________________________ 12. TYPE OF REPORTING PERSON* 00 ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 3 of 12 CUSIP No. 91307C102 13G Page 4 of 12 Pages ________________________________________________________________________________ 1. NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) S.A.C. Capital Associates, LLC ________________________________________________________________________________ 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [X] ________________________________________________________________________________ 3. SEC USE ONLY ________________________________________________________________________________ 4. CITIZENSHIP OR PLACE OF ORGANIZATION Anguilla, British West Indies ________________________________________________________________________________ NUMBER OF 5. SOLE VOTING POWER SHARES 0 _________________________________________________________________ BENEFICIALLY 6. SHARED VOTING POWER OWNED BY 400,000 (see Item 4) _________________________________________________________________ EACH 7. SOLE DISPOSITIVE POWER REPORTING 0 _________________________________________________________________ PERSON 8. SHARED DISPOSITIVE POWER WITH 400,000 (see Item 4) ________________________________________________________________________________ 9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 400,000 (see Item 4) ________________________________________________________________________________ 10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 1.8% (see Item 4) ________________________________________________________________________________ 12. TYPE OF REPORTING PERSON* 00 ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 4 of 12 CUSIP No. 91307C102 13G Page 5 of 12 Pages ________________________________________________________________________________ 1. NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) Sigma Capital Management, LLC ________________________________________________________________________________ 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [X] ________________________________________________________________________________ 3. SEC USE ONLY ________________________________________________________________________________ 4. CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ________________________________________________________________________________ NUMBER OF 5. SOLE VOTING POWER SHARES 0 _________________________________________________________________ BENEFICIALLY 6. SHARED VOTING POWER OWNED BY 1,466,826* (see Item 4) _________________________________________________________________ EACH 7. SOLE DISPOSITIVE POWER REPORTING 0 _________________________________________________________________ PERSON 8. SHARED DISPOSITIVE POWER WITH 1,466,826* (see Item 4) ________________________________________________________________________________ 9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,466,826* (see Item 4) ________________________________________________________________________________ 10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 6.6% (see Item 4) ________________________________________________________________________________ 12. TYPE OF REPORTING PERSON* 00 ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 5 of 12 CUSIP No. 91307C102 13G Page 6 of 12 Pages ________________________________________________________________________________ 1. NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) Sigma Capital Associates, LLC ________________________________________________________________________________ 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [X] ________________________________________________________________________________ 3. SEC USE ONLY ________________________________________________________________________________ 4. CITIZENSHIP OR PLACE OF ORGANIZATION Anguilla, British West Indies ________________________________________________________________________________ NUMBER OF 5. SOLE VOTING POWER SHARES 0 _________________________________________________________________ BENEFICIALLY 6. SHARED VOTING POWER OWNED BY 1,466,826* (see Item 4) _________________________________________________________________ EACH 7. SOLE DISPOSITIVE POWER REPORTING 0 _________________________________________________________________ PERSON 8. SHARED DISPOSITIVE POWER WITH 1,466,826* (see Item 4) ________________________________________________________________________________ 9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,466,826* (see Item 4) ________________________________________________________________________________ 10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 6.6% (see Item 4) ________________________________________________________________________________ 12. TYPE OF REPORTING PERSON* 00 ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 6 of 12 CUSIP No. 91307C102 13G Page 7 of 12 Pages ________________________________________________________________________________ 1. NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY) Steven A. Cohen ________________________________________________________________________________ 2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [X] ________________________________________________________________________________ 3. SEC USE ONLY ________________________________________________________________________________ 4. CITIZENSHIP OR PLACE OF ORGANIZATION United States ________________________________________________________________________________ NUMBER OF 5. SOLE VOTING POWER SHARES 0 _________________________________________________________________ BENEFICIALLY 6. SHARED VOTING POWER OWNED BY 1,866,826* (see Item 4) _________________________________________________________________ EACH 7. SOLE DISPOSITIVE POWER REPORTING 0 _________________________________________________________________ PERSON 8. SHARED DISPOSITIVE POWER WITH 1,866,826* (see Item 4) ________________________________________________________________________________ 9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,866,826* (see Item 4) ________________________________________________________________________________ 10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9) 8.4% (see Item 4) ________________________________________________________________________________ 12. TYPE OF REPORTING PERSON* IN ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! Page 7 of 12 ITEM 1(a) NAME OF ISSUER: United Therapeutics Corporation ITEM 1(b) ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES: 1110 Spring Street Silver Spring, ND 20910 ITEMS 2(a) NAME OF PERSON FILING: This statement is filed by: (i) S.A.C. Capital Advisors, LLC, ("SAC Capital Advisors") with respect to shares of common stock, par value $0.01 per share ("Shares") of the Issuer beneficially owned by S.A.C. Capital Associates, LLC ("SAC Capital Associates"); (ii) S.A.C. Capital Management, LLC, ("SAC Capital Management") with respect to Shares beneficially owned by SAC Capital Associates; (iii) SAC Capital Associates with respect to Shares beneficially owned by it; (iv) Sigma Capital Management, LLC ("Sigma Capital Management") with respect to Shares beneficially owned by Sigma Capital Associates, LLC ("Sigma Capital Associates"); (v) Sigma Capital Associates with respect to Shares beneficially owned by it; and (vi) Steven A. Cohen with respect to Shares beneficially owned by SAC Capital Advisors, SAC Capital Management, SAC Capital Associates, Sigma Capital Management and Sigma Capital Associates. ITEM 2(b) ADDRESS OF PRINCIPAL BUSINESS OFFICE: The address of the principal business office of (i) SAC Capital Advisors and Mr. Cohen is 72 Cummings Point Road, Stamford, Connecticut 06902, (ii) SAC Capital Management and Sigma Capital Management is 540 Madison Avenue, New York, New York 10022, and (iii) SAC Capital Associates, and Sigma Capital Associates is P.O. Box 58, Victoria House, The Valley, Anguilla, British West Indies. ITEM 2(c) CITIZENSHIP: SAC Capital Advisors, SAC Capital Management and Sigma Capital Management are Delaware limited liability companies. SAC Capital Associates, and Sigma Capital Associates are Anguillan limited liability companies. Mr. Cohen is a United States citizen. Page 8 of 12 ITEM 2(d) TITLE OF CLASS OF SECURITIES: Common Stock, par value $0.01 per share ITEM 2(e) CUSIP NUMBER: 91307C102 ITEM 3 Not Applicable ITEM 4 OWNERSHIP: The percentages used herein are calculated based upon the Shares issued and outstanding as of November 1, 2004 as reported on the Issuer's quarterly report on Form 10-Q filed with the Securities and Exchange Commission by the Company for the fiscal year ended December 31, 2004. As of the close of business on December 31, 2004: 1. S.A.C. Capital Advisors, LLC (a) Amount beneficially owned: 400,000 (b) Percent of class: 1.8% (c)(i) Sole power to vote or direct the vote: -0- (ii) Shared power to vote or direct the vote: 400,000 (iii) Sole power to dispose or direct the disposition: -0- (iv) Shared power to dispose or direct the disposition: 400,000 2. S.A.C. Capital Management, LLC (a) Amount beneficially owned: 400,000 (b) Percent of class: 1.8% (c)(i) Sole power to vote or direct the vote: -0- (ii) Shared power to vote or direct the vote: 400,000 (iii) Sole power to dispose or direct the disposition: -0- (iv) Shared power to dispose or direct the disposition: 400,000 3. S.A.C. Capital Associates, LLC (a) Amount beneficially owned: 400,000 (b) Percent of class: 1.8% (c)(i) Sole power to vote or direct the vote: -0- (ii) Shared power to vote or direct the vote: 400,000 (iii) Sole power to dispose or direct the disposition: -0- (iv) Shared power to dispose or direct the disposition: 400,000 Page 9 of 12 4. Sigma Capital Management, LLC (a) Amount beneficially owned: 1,466,826* (b) Percent of class: 6.6% (c)(i) Sole power to vote or direct the vote: 1,466,826* (ii) Shared power to vote or direct the vote: -0- (iii) Sole power to dispose or direct the disposition: -0- (iv) Shared power to dispose or direct the disposition: 1,466,826* 5. Sigma Capital Associates, LLC (a) Amount beneficially owned: 1,466,826* (b) Percent of class: 6.6% (c)(i) Sole power to vote or direct the vote: -0- (ii) Shared power to vote or direct the vote: 1,466,826* (iii) Sole power to dispose or direct the disposition: -0- (iv) Shared power to dispose or direct the disposition: 1,466,826* 6. Steven A. Cohen (a) Amount beneficially owned: 1,866,826* (b) Percent of class: 8.4% (c)(i) Sole power to vote or direct the vote: -0- (ii) Shared power to vote or direct the vote: 1,866,826* (iii) Sole power to dispose or direct the disposition: -0- (iv) Shared power to dispose or direct the disposition: 1,866,826* * The number of shares reported herein includes options held by Sigma Capital Associates on 225,000 Shares. SAC Capital Advisors, SAC Capital Management, Sigma Capital Management, and Mr. Cohen own directly no Shares. Pursuant to investment agreements, each of SAC Capital Advisors and SAC Capital Management share all investment and voting power with respect to the securities held by SAC Capital Associates. Pursuant to an investment management agreement, Sigma Capital Management maintains investment and voting power with respect to the securities held by Sigma Capital Associates. Mr. Cohen controls each of SAC Capital Advisors, SAC Capital Management and Sigma Capital Management. By reason of the provisions of Rule 13d-3 of the Securities Exchange Act of 1934, as amended, each of (i) SAC Capital Advisors, SAC Capital Management and Mr. Cohen may be deemed to own beneficially 400,000 Shares (constituting approximately 1.8% of the Shares outstanding) and (ii) Sigma Capital Management and Mr. Cohen may be deemed to own beneficially 1,466,826 shares (constituting approximately 6.6% of the Shares outstanding). Each of SAC Capital Advisors, SAC Capital Management, Sigma Capital Management and Mr. Cohen disclaim beneficial ownership of any of the securities covered by this statement. Page 10 of 12 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: Not Applicable ITEM 9 NOTICE OF DISSOLUTION OF GROUP: Not Applicable ITEM 10 CERTIFICATION: By signing below the signatory certifies that, to the best of his 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. Page 11 of 12 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: February 14, 2005 S.A.C. CAPITAL ADVISORS, LLC By: /s/ Peter Nussbaum ----------------------------------------- Name: Peter Nussbaum Title: Authorized Person S.A.C. CAPITAL MANAGEMENT, LLC By: /s/ Peter Nussbaum ----------------------------------------- Name: Peter Nussbaum Title: Authorized Person S.A.C. CAPITAL ASSOCIATES, LLC By: /s/ Peter Nussbaum ----------------------------------------- Name: Peter Nussbaum Title: Authorized Person SIGMA CAPITAL MANAGEMENT, LLC By: /s/ Peter Nussbaum ----------------------------------------- Name: Peter Nussbaum Title: Authorized Person SIGMA CAPITAL ASSOCIATES, LLC By: /s/ Peter Nussbaum ----------------------------------------- Name: Peter Nussbaum Title: Authorized Person STEVEN A. COHEN By: /s/ Peter Nussbaum ----------------------------------------- Name: Peter Nussbaum Title: Authorized Person Page 12 of 12