Item 1.01 Entry into a Material Definitive Agreement

Quest Diagnostics Incorporated, a Delaware corporation (“Quest Diagnostics”), Ace Acquisition Sub, Inc., a Delaware corporation and a wholly owned subsidiary of Quest Diagnostics (“Merger Sub”), and AmeriPath Group Holdings, Inc., a Delaware corporation (“AmeriPath”), have entered into a definitive Agreement and Plan of Merger dated as of April 15, 2007 (the “Merger Agreement”). The Merger Agreement provides that, upon the terms and subject to the conditions set forth in the Merger Agreement, Merger Sub will merge with and into AmeriPath, with AmeriPath continuing as the surviving corporation and a wholly-owned subsidiary of Quest Diagnostics (the “Merger”). Welsh, Carson, Anderson & Stowe IX, L.P., as the holder of a majority of the outstanding shares of Common Stock and Participating Preferred Stock of AmeriPath, has executed a written consent of stockholders dated as of April 16, 2007 approving the form, terms and provisions of the Merger Agreement. No further consents of stockholders are necessary to adopt the Merger Agreement.

The consideration to be paid by Quest Diagnostics at the closing pursuant to the Merger Agreement will be (a) $2 billion, plus (b) the amount of Specified Cash (as defined in the Merger Agreement, representing AmeriPath’s unrestricted cash balance), less (c) the amount of indebtedness (including in certain cases accrued interest and/or premium) of AmeriPath as of the closing date, less (d) the amount of the Transaction Expenses (as defined in the Merger Agreement) of AmeriPath and its majority stockholder, plus (e) the aggregate exercise price of AmeriPath’s stock options that are vested as of the closing date.

Pursuant to the Merger Agreement, at the effective time of the Merger, each issued and outstanding share of common stock and participating preferred stock of AmeriPath (the “Shares”), other than any Shares owned by AmeriPath or by any of its subsidiaries and any Shares owned by Quest Diagnostics or Merger Sub, shall be canceled and converted into the right to receive a pro rata portion of the aggregate merger consideration as determined under the Merger Agreement (the “Per Share Merger Consideration”). Each holder of an option to purchase Shares granted under AmeriPath’s stock option plan that is vested as of the closing (a “Vested Stock Option”) shall be entitled, at the closing, to receive cash equal to the Per Share Merger Consideration less the exercise price of such Vested Stock Option. Each holder of an option to purchase Shares granted under AmeriPath’s stock option plan that is not vested as of the closing shall be canceled and exchanged for an option to purchase common stock of Quest Diagnostics pursuant to the terms of the Merger Agreement.

The transaction is expected to be completed during the second quarter of 2007 and is subject to the satisfaction of customary conditions, including expiration or termination of the Hart-Scott-Rodino waiting period.

A copy of the Merger Agreement is filed as Exhibit 10.1 hereto, and is incorporated into this report by reference. The description of the Merger and the Merger Agreement is qualified in its entirety by reference to the Merger Agreement.

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