Explanatory Notes  

Item 1.      Security and Issuer.

   The name of the issuer is Magellan Health Services, Inc., a Delaware corporation (the "Issuer"). The address of the Issuer’s principal executive offices is 55 Nod Road, Avon, Connecticut 06001. This Schedule 13D relates to the Issuer’s ordinary common stock, par value $0.01 per share (the "Common Stock").

Item 2.      Identity and Background.

   (a)-(c), (f).  This Schedule 13D is being filed by Integrated Core Strategies (US) LLC, a Delaware limited liability company ("Integrated Core Strategies"), Millenco LLC, a Delaware limited liability company ("Millenco"), ICS Opportunities, Ltd., an exempted limited company organized under the laws of the Cayman Islands ("ICS Opportunities") and Cognizant Holdings, Ltd., an exempted limited company organized under the laws of the Cayman Islands ("Cognizant Holdings"). Millenco is a broker-dealer and a member of the American Stock Exchange and the NASDAQ.

   Millennium Management LLC, a Delaware limited liability company ("Millennium Management"), is the general partner of the managing member of Integrated Core Strategies, and may be deemed to have shared voting control and investment discretion over securities owned by Integrated Core Strategies. Millennium Management is also the manager of Millenco, and may be deemed to have shared voting control and investment discretion over securities owned by Millenco. Millennium Management is also the general partner of the 100% shareholder of ICS Opportunities and Cognizant Holdings, and consequently may be deemed to have shared voting control and investment discretion over securities owned by ICS Opportunities or Cognizant Holdings, as the case may be.

   Millennium International Management LP, a Delaware limited partnership ("Millennium International Management"), is the investment manager to ICS Opportunities and Cognizant Holdings, and may be deemed to have shared voting control and investment discretion over securities owned by ICS Opportunities or Cognizant Holdings, as the case may be. Millennium International Management GP LLC, a Delaware limited liability company ("Millennium International Management GP"), is the general partner of Millennium International Management, and may also be deemed to have shared voting control and investment discretion over securities owned by ICS Opportunities or Cognizant Holdings, as the case may be.

   Israel A. Englander, a United States citizen ("Mr. Englander"), is the managing member of Millennium Management and of Millennium International Management GP, and consequently may also be deemed to be the beneficial owner of any securities owned by Integrated Core Strategies, Millenco, ICS Opportunities or Cognizant Holdings, as the case may be.

   The foregoing should not be construed in and of itself as an admission by Millennium Management, Millennium International Management, Millennium International Management GP or Mr. Englander as to beneficial ownership of the securities owned by Integrated Core Strategies, Millenco, ICS Opportunities or Cognizant Holdings, as the case may be.

   Integrated Core Strategies, Millenco, ICS Opportunities, Cognizant Holdings, Millennium International Management and Millennium International Management GP and Mr. Englander will be collectively referred to as the reporting persons ("Reporting Persons") in this Schedule 13D.

   The business address for Integrated Core Strategies, Millenco and Mr. Englander is c/o Millennium Management LLC, 666 Fifth Avenue, New York, New York 10103. The business address for ICS Opportunities and Cognizant Holdings is c/o Millennium International Management LP, 666 Fifth Avenue, New York, New York 10103. The business address for Millennium International Management is c/o Millennium International Management GP LLC, 666 Fifth Avenue, New York, New York 10103. The business address for Millennium International Management GP and Millennium Management is 666 Fifth Avenue, New York, New York 10103.

   (d)  During the last five years, none of the Reporting Persons has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors).

   (e)  On December 1, 2005, Millennium Management and Mr. Englander, together with Millennium Partners, L.P. ("Millennium Partners") and certain related persons and entities, entered into settlements with the Securities and Exchange Commission ("SEC") and the Attorney General of the State of New York (the "NYAG") relating to allegations that Millennium Partners had engaged in a pattern of deceptive "market timing" of mutual fund shares in years prior to 2004 and, in the case of the settlement with the NYAG only, had failed to take adequate steps to prevent a trader from engaging in mutual fund "late trading" in violation of firm policy. The parties neither admitted nor denied the allegations or findings (except as to jurisdiction) but consented to the entry of findings. The SEC proceedings are In the Matter of Millennium Partners, L.P., et al. Securities Act Release No. 8639 (December 1, 2005), available at www.sec.gov. Contemporaneously, the NYAG issued an Assurance of Discontinuance relating to the claims and findings of that office.

   Neither the Reporting Persons nor any other party admitted or denied any of the allegations or findings in these matters. The remedies included disgorgement by the entities of approximately $148 million of mutual fund trading profits, civil penalties aggregating approximately $32.15 million (with approximately $30 million being paid by Mr. Englander), an administrative order to cease and desist from violations of the antifraud provisions of the Securities Act of 1933 and the Securities Exchange Act of 1934 (the "Exchange Act"), and prophylactic relief.

Item 3.      Source and Amount of Funds or Other Consideration.

   The amount of funds used to purchase the 1,649,582 shares of the Issuer’s Common Stock held by Integrated Core Strategies was approximately $63,694,810 calculated on an average cost basis (excluding brokerage commissions) by account. The amount of funds used to purchase the 129,021 shares of the Issuer’s Common Stock held by Millenco was approximately $5,601,770 calculated on an average cost basis (excluding brokerage commissions) by account. The amount of funds used to purchase the 108,772 shares of the Issuer’s Common Stock held by ICS Opportunities was approximately $3,909,273 calculated on an average cost basis (excluding brokerage commissions) by account. The amount of funds used to purchase the 312 shares of the Issuer’s Common Stock held by Cognizant Holdings was approximately $13,561 calculated on an average cost basis (excluding brokerage commissions) by account. Integrated Core Strategies, Millenco, ICS Opportunities and Cognizant Holdings effect purchases of securities primarily through margin accounts maintained for them with prime brokers, which may extend margin credit to Integrated Core Strategies, Millenco, ICS Opportunities and Cognizant Holdings as and when required to open or carry positions in the margin accounts, subject to applicable margin regulations, stock exchange rules and the prime broker’s credit policies. In such instances, the positions held in the margin accounts are pledged as collateral security for the repayment of debit balances in the accounts.

Item 4.       Purpose of Transaction.

   The Reporting Persons are engaged in the investment business, and in the course of that business employ the services of a number of portfolio managers, each of whom independently employs a separate and distinct trading strategy. A portion of the securities of the Issuer held by the Reporting Persons may be managed by portfolio managers who engage in event-, risk- or merger-arbitrage or fundamental strategies.

   In pursuing their business, some of the Reporting Persons’ portfolio managers analyze the operations, capital structure and markets of companies, including the Issuer, on a continuous basis, through analysis of documentation and discussions with knowledgeable industry and market observers and with representatives of such companies (often at the invitation of management). (Other portfolio managers, who may also have long or short positions in securities of the Issuer from time to time, trade pursuant to quantitative or other strategies that do not involve such analyses and discussions.) From time to time, one or more of the portfolio managers may hold discussions with third parties or with management of issuers (including the Issuer) in which the portfolio managers may suggest or take a position with respect to potential changes in the operations, management or capital structure of such companies as a means of enhancing shareholder value. Such suggestions or positions may relate to one or more transactions of the type specified in clauses (a) through (j) of Item 4 of Schedule 13D of the Exchange Act, including, without limitation, such matters as disposing of or selling all or a portion of the company or acquiring another company or business, changing operating or marketing strategies, adopting or not adopting certain types of anti-takeover measures and restructuring the Issuer’s capitalization or dividend policy.

   Except as set forth above, the Reporting Persons do not have any present plans or proposals that relate to or would result in any of the actions required to be described in Item 4 of this Schedule 13D. Each of the Reporting Persons may, at any time, review or reconsider its position with respect to the Issuer and formulate plans or proposals with respect to any of such matters, but has no present intention of doing so.

Item 5.      Interest in Securities of the Issuer.

   (a)  As of the date of this Schedule 13D: i) Integrated Core Strategies is the beneficial owner of 1,649,582 shares of the Issuer’s Common Stock; ii) Millenco is the beneficial owner of 129,021 shares of the Issuer’s Common Stock; iii) ICS Opportunities is the beneficial owner of 108,772 shares of the Issuer’s Common Stock; and iv) Cognizant Holdings is the beneficial owner of 312 shares of the Issuer’s Common Stock

   Millennium Management, as the general partner of the managing member of Integrated Core Strategies, may be deemed to have shared voting control and investment discretion over securities owned by Integrated Core Strategies. Millennium Management, as the manager of Millenco, may be deemed to have shared voting control and investment discretion over securities owned by Millenco. Millennium Management, as the general partner of the 100% shareholder of ICS Opportunities and Cognizant Holdings, may be deemed to have shared voting control and investment discretion over securities owned by ICS Opportunities or Cognizant Holdings, as the case may be.

   Millennium International Management, as the investment manager to ICS Opportunities and Cognizant Holdings, may be deemed to have shared voting control and investment discretion over securities owned by ICS Opportunities or Cognizant Holdings, as the case may be. Millennium International Management GP, as the general partner of Millennium International Management, may also be deemed to have shared voting control and investment discretion over securities owned by ICS Opportunities or Cognizant Holdings, as the case may be.

   Mr. Englander, as the managing member of Millennium Management and of Millennium International Management GP, may also be deemed to be the beneficial owner of any securities owned by Integrated Core Strategies, Millenco, ICS Opportunities or Cognizant Holdings, as the case may be.

   Accordingly, as of the date of this Schedule 13D, Millennium Management and Mr. Englander may be deemed to beneficially own approximately 1,887,687 shares or approximately 5.7% of the Issuer’s Common Stock. The calculation of the foregoing percentage is on the basis of 33,337,110 shares of Common Stock outstanding as of March 31, 2010, as per the Issuer’s Proxy Statement dated April 7, 2010.

   The foregoing should not be construed in and of itself as an admission by Millennium Management, Millennium International Management, Millennium International Management GP or Mr. Englander as to beneficial ownership of the securities owned by Integrated Core Strategies, Millenco, ICS Opportunities or Cognizant Holdings, as the case may be.

   (b)  Integrated Core Strategies holds shared power to vote and dispose of 1,649,582 shares of the Issuer’s Common Stock described in (a) above. Millenco holds shared power to vote and dispose of 129,021 shares of the Issuer’s Common Stock described in (a) above. ICS Opportunities holds shared power to vote and dispose of 108,772 shares of the Issuer’s Common Stock described in (a) above. Cognizant Holdings holds shared power to vote and dispose of 312 shares of the Issuer’s Common Stock described in (a) above. Millennium International Management and Millennium International Management GP may be deemed to hold shared power to vote and to dispose of the 109,084 shares of the Issuer’s Common Stock described in (a) above. Millennium Management and Mr. Englander may be deemed to hold shared power to vote and to dispose of the 1,887,687 shares of the Issuer’s Common Stock described in (a) above. The foregoing should not be construed in and of itself as an admission by Millennium Management, Millennium International Management, Millennium International Management GP or Mr. Englander as to beneficial ownership of the securities owned by Integrated Core Strategies, Millenco, ICS Opportunities or Cognizant Holdings, as the case may be.

   (c)  Transactions in the Issuer’s Common Stock during the past 60 days: Schedule A annexed hereto lists all transactions in the Issuer’s Common Stock effected by the Reporting Persons during the past 60 days. All such transactions in the Issuer’s Common Stock were effected by either Integrated Core Strategies, Millenco, ICS Opportunities or Cognizant Holdings in the open market.

   (d)  No person other than the Reporting Persons is known to have the right to receive, or the power to direct the receipt of, dividends from, or proceeds from the sale of, the shares of the Issuer’s Common Stock reported in this Schedule 13D.

Item 6.      Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer.

   Millenco maintains an open short position of 2,263 shares of the Issuer’s Common Stock, which position is not netted against the data provided herein as to the number of shares beneficially owned by the Reporting Persons.

   In connection with arrangements with Integrated Core Strategies’, Millenco’s, ICS Opportunities’ and Cognizant Holdings’ prime brokers, such prime brokers are permitted to lend securities in Integrated Core Strategies’, Millenco’s, ICS Opportunities’ and Cognizant Holdings’ accounts to the extent permitted by debit balances in such accounts. Integrated Core Strategies, Millenco, ICS Opportunities and Cognizant Holdings generally will not have any knowledge of the specific loans made by such prime brokers. In the ordinary course of business, Integrated Core Strategies, Millenco, ICS Opportunities and Cognizant Holdings (or their prime brokers), may borrow securities to satisfy delivery obligations arising from short sales. In addition, Millenco may lend securities to third parties and such loans generally may be recalled upon demand. However, it should be noted that shares lent by Integrated Core Strategies’, Millenco’s, ICS Opportunities’ and Cognizant Holdings’ prime brokers, or by Millenco, may not be able to be recalled in advance of an applicable record date and thus, such loaned shares may not be able to be voted by Integrated Core Strategies, Millenco, ICS Opportunities, or Cognizant Holdings, as the case may be. As of the date this Schedule 13D, Millenco has lent 9,200 shares of the Issuer’s Common Stock to third parties.

   There are no other contracts, arrangements, understandings or relationships among the Reporting Persons, or between the Reporting Persons and any other person, with respect to the securities of the Issuer.

Item 7.      Material to Be Filed as Exhibits.

   Exhibit I:  Joint Filing Agreement, dated as of April 8, 2010, by and among Integrated Core Strategies (US) LLC, Millenco LLC, ICS Opportunities, Ltd., Cognizant Holdings, Ltd., Millennium International Management LP, Millennium International Management GP LLC, Millennium Management LLC and Israel A. Englander.

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.