UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13D UNDER THE SECURITIES EXCHANGE ACT OF 1934 (AMENDMENT NO. 1) Magellan Health Services Inc. ---------------------------------------------------------------------- (Name of Issuer) Common Stock, $0.01 Par Value Per Share ---------------------------------------------------------------------- (Title Class of Securities) 559079207 ---------------------------------------------------------------------- (CUSIP Number) HealthCor Management, L.P. Carnegie Hall Tower 152 West 57th Street, 47th Floor New York, New York 10019 Attention: Mr. Steven J. Musumeci (212) 622-7888 With a Copy to: Marc Weingarten Schulte Roth & Zabel LLP 919 Third Avenue New York, New York 10022 (212) 756-2280 ---------------------------------------------------------------------- (Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) November 4, 2008 ---------------------------------------------------------------------- (Date of Event which Requires Filing of this Statement) If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of ss.ss.240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. [X] CUSIP NO. 559079207 13D/A Page 2 of 13 Pages -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION OF ABOVE PERSON HealthCor Management, L.P. 20-2893581 -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [x] (b) [ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS WC -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) [ ] -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware -------------------------------------------------------------------------------- 7 SOLE VOTING POWER NUMBER OF 0 SHARES ------------------------------------------------------------ BENEFICIALLY 8 SHARED VOTING POWER OWNED BY 3,200,000 EACH ------------------------------------------------------------ REPORTING 9 SOLE DISPOSITIVE POWER PERSON WITH 0 ------------------------------------------------------------ 10 SHARED DISPOSITIVE POWER 3,200,000 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,200,000 -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [ ] -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 7.91% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON PN -------------------------------------------------------------------------------- CUSIP NO. 559079207 13D/A Page 3 of 13 Pages -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION OF ABOVE PERSON HealthCor Associates, LLC 20-2891849 -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [x] (b) [ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* AF -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) [ ] -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware -------------------------------------------------------------------------------- 7 SOLE VOTING POWER NUMBER OF 0 SHARES ------------------------------------------------------------ BENEFICIALLY 8 SHARED VOTING POWER OWNED BY 3,200,000 EACH ------------------------------------------------------------ REPORTING 9 SOLE DISPOSITIVE POWER PERSON WITH 0 ------------------------------------------------------------ 10 SHARED DISPOSITIVE POWER 3,200,000 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,200,000 -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [ ] -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 7.91% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON OO- limited liability company -------------------------------------------------------------------------------- CUSIP NO. 559079207 13D/A Page 4 of 13 Pages -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION OF ABOVE PERSON HealthCor Offshore, Ltd. N/A -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [x] (b) [ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS AF -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) [ ] -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION Cayman Islands -------------------------------------------------------------------------------- 7 SOLE VOTING POWER NUMBER OF 0 SHARES ------------------------------------------------------------ BENEFICIALLY 8 SHARED VOTING POWER OWNED BY 2,159,513 EACH ------------------------------------------------------------ REPORTING 9 SOLE DISPOSITIVE POWER PERSON WITH 0 ------------------------------------------------------------ 10 SHARED DISPOSITIVE POWER 2,159,513 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 2,159,513 -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [ ] -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 5.34% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON OO-limited company -------------------------------------------------------------------------------- CUSIP NO. 559079207 13D/A Page 5 of 13 Pages -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION OF ABOVE PERSON HealthCor Hybrid Offshore, Ltd. N/A -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [x] (b) [ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS AF -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) [ ] -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION Cayman Islands -------------------------------------------------------------------------------- 7 SOLE VOTING POWER NUMBER OF 0 SHARES ------------------------------------------------------------ BENEFICIALLY 8 SHARED VOTING POWER OWNED BY 402,898 EACH ------------------------------------------------------------ REPORTING 9 SOLE DISPOSITIVE POWER PERSON WITH 0 ------------------------------------------------------------ 10 SHARED DISPOSITIVE POWER 402,898 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 402,898 -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [ ] -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 1.0% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON OO-limited company -------------------------------------------------------------------------------- CUSIP NO. 559079207 13D/A Page 6 of 13 Pages -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION OF ABOVE PERSON HealthCor Group, LLC 51-0551771 -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [x] (b) [ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS AF -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) [ ] -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware -------------------------------------------------------------------------------- 7 SOLE VOTING POWER NUMBER OF 0 SHARES ------------------------------------------------------------ BENEFICIALLY 8 SHARED VOTING POWER OWNED BY 637,589 EACH ------------------------------------------------------------ REPORTING 9 SOLE DISPOSITIVE POWER PERSON WITH 0 ------------------------------------------------------------ 10 SHARED DISPOSITIVE POWER 637,589 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 637,589 -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [ ] -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 1.58% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON OO-limited liability company -------------------------------------------------------------------------------- CUSIP NO. 559079207 13D/A Page 7 of 13 Pages -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION OF ABOVE PERSON HealthCor Capital, L.P. 51-0551770 -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [x] (b) [ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS AF -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) [ ] -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware -------------------------------------------------------------------------------- 7 SOLE VOTING POWER NUMBER OF 0 SHARES ------------------------------------------------------------ BENEFICIALLY 8 SHARED VOTING POWER OWNED BY 637,589 EACH ------------------------------------------------------------ REPORTING 9 SOLE DISPOSITIVE POWER PERSON WITH 0 ------------------------------------------------------------ 10 SHARED DISPOSITIVE POWER 637,589 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 637,589 -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [ ] -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 1.58% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON PN -------------------------------------------------------------------------------- CUSIP NO. 559079207 13D/A Page 8 of 13 Pages -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION OF ABOVE PERSON HealthCor L.P. 20-3240266 -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) [x] (b) [ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS AF -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) [ ] -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware -------------------------------------------------------------------------------- 7 SOLE VOTING POWER NUMBER OF 0 SHARES ------------------------------------------------------------ BENEFICIALLY 8 SHARED VOTING POWER OWNED BY 637,589 EACH ------------------------------------------------------------ REPORTING 9 SOLE DISPOSITIVE POWER PERSON WITH 0 ------------------------------------------------------------ 10 SHARED DISPOSITIVE POWER 637,589 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 637,589 -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [ ] -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 1.58% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON PN -------------------------------------------------------------------------------- CUSIP NO. 559079207 13D/A Page 9 of 13 Pages -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION OF ABOVE PERSON Arthur Cohen -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [x] (b) [ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* AF -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) [ ] -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION United States -------------------------------------------------------------------------------- 7 SOLE VOTING POWER NUMBER OF 0 SHARES ------------------------------------------------------------ BENEFICIALLY 8 SHARED VOTING POWER OWNED BY 3,200,000 EACH ------------------------------------------------------------ REPORTING 9 SOLE DISPOSITIVE POWER PERSON WITH 0 ------------------------------------------------------------ 10 SHARED DISPOSITIVE POWER 3,200,000 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,200,000 -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [ ] -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 7.91% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON IN -------------------------------------------------------------------------------- CUSIP NO. 559079207 13D/A Page 10 of 13 Pages -------------------------------------------------------------------------------- 1 NAME OF REPORTING PERSON S.S. OR I.R.S. IDENTIFICATION OF ABOVE PERSON Joseph Healey -------------------------------------------------------------------------------- 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [x] (b) [ ] -------------------------------------------------------------------------------- 3 SEC USE ONLY -------------------------------------------------------------------------------- 4 SOURCE OF FUNDS* AF -------------------------------------------------------------------------------- 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(D) OR 2(E) [ ] -------------------------------------------------------------------------------- 6 CITIZENSHIP OR PLACE OF ORGANIZATION United States -------------------------------------------------------------------------------- 7 SOLE VOTING POWER NUMBER OF 0 SHARES ------------------------------------------------------------ BENEFICIALLY 8 SHARED VOTING POWER OWNED BY 3,200,000 EACH ------------------------------------------------------------ REPORTING 9 SOLE DISPOSITIVE POWER PERSON WITH 0 ------------------------------------------------------------ 10 SHARED DISPOSITIVE POWER 3,200,000 -------------------------------------------------------------------------------- 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,200,000 -------------------------------------------------------------------------------- 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [ ] -------------------------------------------------------------------------------- 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 7.91% -------------------------------------------------------------------------------- 14 TYPE OF REPORTING PERSON IN -------------------------------------------------------------------------------- CUSIP NO. 559079207 13D/A Page 11 of 13 Pages The Schedule 13D filed by the Reporting Persons on March 17, 2008 relating to the shares ("Shares") of common stock, $0.01 par value, of Magellan Health Services Inc. is hereby amended as set forth below by this Amendment No. 1 to the Schedule 13D. ITEM 3. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION Item 3 of the Schedule 13D is hereby amended as follows: The total amount HealthCor has paid for the 3,200,000 Shares reported herein is approximately $126,674,048.31. The Shares were paid for by cash provided by the HealthCor Funds that are managed by HealthCor Management, L.P. Such cash consists of capital contributions from investors in the HealthCor Funds and the capital appreciation thereon. ITEM 5. INTEREST IN SECURITIES OF THE ISSUER Subsections (a) and (c) of Item 5 of the Schedule 13D are hereby amended as follows: (a) As of November 4, 2008, the Reporting Persons beneficially owned in the aggregate 3,200,000 Shares which represents approximately 7.91% of the Issuer's Common Stock outstanding. The aggregate percentage beneficially owned by the Reporting Persons is based upon 40,453,168 Shares of the Issuer issued and outstanding as of September 30, 2007, as reported in the Issuer's 10-Q filed for the quarterly period ended September 30, 2008. (c) The following transactions in the Shares were effected by the Reporting Persons during the past 60 days, each of which was effected in open market transactions. HealthCor, L.P. Trade Shares Price per Date Purchased(Sold) Share 10/31/2008 1,043 $34.10 10/31/2008 28,859 36.03 11/04/2008 10,072 34.67 CUSIP NO. 559079207 13D/A Page 12 of 13 Pages HealthCor Offshore, Ltd. Trade Shares Price per Date Purchased(Sold) Share 10/31/2008 3,535 $34.10 10/31/2008 97,757 36.03 11/04/2008 33,616 34.67 HealthCor Hybrid Offshore, Ltd. Trade Shares Price per Date Purchased(Sold) Share 10/31/2008 657 $34.10 10/31/2008 18,149 36.03 11/04/2008 6,312 34.67 CUSIP NO. 559079207 13D/A Page 13 of 13 Pages 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. Date: November 6, 2008 HEALTHCOR MANAGEMENT, L.P., FOR ITSELF HEALTHCOR ASSOCIATES, LLC AND AS MANAGER ON BEHALF OF (I) HEALTHCOR OFFSHORE, LTD. AND (II) HEALTHCOR HYBRID OFFSHORE, LTD. By: /s/ Steven J. Musumeci ------------------------------ By: HealthCor Associates, LLC, its general Name: Steven J. Musumeci partner Title: Chief Operating Officer By: /s/ Steven J. Musumeci ------------------------------ Name: Steven J. Musumeci HEALTHCOR GROUP, LLC Title: Chief Operating Officer By:/s/ Steven J. Musumeci ------------------------------- HEALTHCOR CAPITAL, L.P., FOR ITSELF AND Name: Steven J. Musumeci AS GENERAL PARTNER ON BEHALF OF Title: Chief Operating Officer HEALTHCOR, L.P. By: HealthCor Group, LLC, its general /s/ Joseph Healey partner ---------------------------------- JOSEPH HEALEY, Individually By: /s/ Steven J. Musumeci ------------------------------ /s/ Arthur Cohen Name: Steven J. Musumeci ---------------------------------- Title: Chief Operating Officer ARTHUR COHEN, Individually