S-P Supplemental Indenture

Effective as of the Closing Date, Old Merck and New Merck executed and delivered to The Bank of New York Mellon (the "S-P Trustee"), a Fifth Supplemental Indenture, dated as of the Closing Date (the "Fifth Supplemental Indenture") in accordance with that certain indenture dated November 26, 2003 (the "S-P Indenture") between New Merck and the S-P Trustee, pursuant to which Old Merck fully and unconditionally guaranteed (a) the full and punctual payment when due of all obligations of New Merck, whether for payment of principal, interest or premium on the S-P Notes (described below) when due, and all other monetary obligations of the New Merck under the S-P Indenture and the S-P Notes, and
(b) the full and punctual performance with applicable grace periods of all other obligations of New Merck under the S-P Notes.

The "S-P Notes" consist of the following six outstanding series of notes issued by Schering-Plough under the Indenture prior to the Mergers (collectively, the "S-P Notes"):

1. $1,250,000,000 5.30% Notes due 2013, issued pursuant to a First Supplemental Indenture, dated as of November 26, 2003;

2. $1,150,000,000 6.50% Notes due 2033, issued pursuant to a Second Supplemental Indenture, dated as of November 26, 2003;

3. $1,000,000,000 6.00% Notes due 2017, issued pursuant to a Third Supplemental Indenture, dated as of September 17, 2007;

4. $1,000,000,000 6.55% Notes due 2037, issued pursuant to a Third Supplemental Indenture, dated as of September 17, 2007;

5. €500,000,000 5.000% Senior Notes due 2010, issued pursuant to a Fourth Supplemental Indenture, dated as of October 1, 2007; and

6. €1,500,000,000 5.375% Senior Notes due 2014, issued pursuant to the Fourth Supplemental Indenture, dated as of October 1, 2007.

Copies of the Indenture, the First Supplemental Indenture, the Second Supplemental Indenture, the Third Supplemental Indenture, the Fourth Supplemental Indenture and the Fifth Supplemental Indenture are attached hereto as Exhibits 4.1, 4.2, 4.3, 4.4, 4.5 and 4.6, respectively. The description of the S-P Notes and the guarantee described above is qualified in its entirety by reference to the full text of the Indenture, the First Supplemental Indenture, the Second Supplemental Indenture, the Third Supplemental Indenture, the Fourth Supplemental Indenture and the Fifth Supplemental Indenture.

Merck Supplemental Indenture

S-P Supplemental Indenture

Effective as of the Closing Date, Old Merck unconditionally guaranteed the full and punctual payment of principal of, and interest on, and all other amounts due under the S-P Notes. As of September 30, 2009, there was $4,400,000,000 and €2,000,000,000 in aggregate principal amount of S-P Notes outstanding. See the disclosure set forth under "S-P Supplemental Indenture" in Item 1.01 above, which is incorporated by reference herein.

(d) Notice of Delisting of Shares of Old Merck Common Stock

On the Closing Date, Old Merck notified the New York Stock Exchange ("NYSE") of the anticipated closing date of the Mergers and requested that after the consummation of the Mergers the NYSE file with the Securities and Exchange Commission (the "SEC") an application on Form 25 to strike the common stock, par value $0.01 per share, of Old Merck ("Old Merck Common Stock") from listing on the NYSE. Under the rules of the SEC, the application on Form 25 will be effective 10 days after filing with the SEC, unless the effectiveness is postponed by the SEC.

In connection with the Mergers, Old Merck issued 100 shares of common stock, representing 100 percent of the capital stock of Old Merck, to New Merck. This issuance is exempt from the registration requirements of the Securities Act of 1933, as amended, pursuant to Section 4(2) thereof.

On the Closing Date, as a result of the Mergers, a change of control of Old Merck occurred and Old Merck became a wholly owned subsidiary of New Merck.

Pursuant to the Mergers, each outstanding share of Old Merck Common Stock immediately prior to the Mergers was converted into one share of common stock, par value $0.50 per share, of New Merck ("New Merck Common Stock").

The description of the Merger Agreement contained in this Item 5.01 does not purport to be complete and is subject to and qualified in its entirety by reference to the Merger Agreement, a copy of which is attached hereto as Exhibit 2.1 and the terms of which are incorporated herein by reference.

(b) Resignations and Terminations of Certain Officers and Directors

Effective as of the Closing Date, all of the directors of Old Merck became directors of New Merck, the new parent company of Old Merck, and (other than Richard T. Clark) are no longer directors of Old Merck.

(d) Appointment of Directors

Effective as of the Closing Date, the following individuals, each of whom is an officer of New Merck and Old Merck, were elected to serve as directors of Old Merck, together with Richard T. Clark: Kenneth C. Frazier, Peter N. Kellogg and Bruce N. Kuhlik. Following the Closing Date, the individuals serving as members of the Board of Directors of Old Merck will not receive any separate compensation for their role as a director of Old Merck.

(e) Compensatory Agreements and Arrangements

Compensation of Named Executive Officers

No changes were made in connection with the Mergers to the total compensation packages of the executives who served as the named executive officers of Old Merck immediately prior to the Closing Date; however, certain compensatory plans and arrangements of Old Merck were amended, or amended and restated, to reflect the new corporate structure as a result of the Mergers and to make technical changes deemed necessary for the continued operation of such plans following the Mergers, as described below. In addition, certain plans, including equity compensation plans, were assumed by New Merck. Those individuals who served as named executive officers of Old Merck, as well as all other Old Merck executives and employees continue to be compensated through their participation in the compensatory programs, policies and plans sponsored by Old Merck, as a wholly-owned subsidiary of New Merck as of the Closing Date. Generally, all terms and conditions that applied to any element of compensation immediately before the Mergers (which have been disclosed, as required, as part of Old Merck's current, periodic and annual fillings) will continue to apply following the Closing Date.

The amendments to the relevant plans, including, generally, cash and non-cash incentive compensation plans, certain change in control and severance compensation arrangements, deferred compensation plans, are briefly described below.

Long Term Incentives: Old Merck amended and restated as of the Closing Date the Merck Sharp & Dohme Corp. 2007 Incentive Stock Plan (formerly known as the Merck & Co., Inc. 2007 Incentive Stock Plan) (the "MSD 2007 ISP"). The MSD 2007 ISP was assumed by New Merck, effective as of the Closing Date. A copy of the MSD 2007 ISP, as amended, is attached hereto as Exhibit 10.1. The MSD 2007 ISP is substantially the same as the Old Merck 2007 Incentive Stock Plan (the "Prior 2007 ISP"), which was approved by the shareholders of Old Merck on April 25, 2006, except with respect to the following:

• administration of the MSD 2007 ISP by the Board of Directors of New Merck ("New Merck Board") and its Compensation & Benefits Committee rather than by the Board of Directors of Old Merck ("Old Merck Board") and its Compensation & Benefits Committee;

• the definition of change in control, as described in the New Merck Change in Control Separation Benefits Plan, as described below, applies generally to a change in control of New Merck rather than a change in control of Old Merck, although for incentive awards outstanding on the Closing Date, a change in control of Old Merck (as it was defined in the Old Merck Change in Control Separation Benefits Plan prior to the Mergers) will also apply; and

• limited modifications deemed necessary to reflect the fact that Old Merck is now one of a number of wholly-owned subsidiaries of New Merck.

MSD Awards Outstanding on the Closing Date: Effective as of the Closing Date, Old Merck amended several of its equity incentive plans including: (a) Merck Sharp & Dohme Corp. 2004 Incentive Stock Plan; (b) Merck Sharp & Dohme Corp. 2001 Incentive Stock Plan; (c) Merck Sharp & Dohme Corp. 1996 Incentive Stock Plan; (d) Merck & Co., Inc. 2001 Non-Employee Director Stock Option Plan; and
(e) Merck & Co., Inc. 1996 Non-Employee Director Stock Option Plan, to reflect the Mergers. These plans, together with the Rosetta Inpharmatics, Inc. 2000 Stock Plan and Rosetta Inpharmatics, Inc. 1996 Stock Plan were assumed by New Merck (all plans together, the "MSD Prior Equity Plans"). The amendments, applicable to the relevant plans, are attached hereto as Exhibits 10.2 to 10.6.

The MSD Prior Equity Plans were no longer being used by Old Merck immediately prior to the Mergers to grant new awards and no new awards will be granted pursuant to any of the MSD Prior Equity Plans following the Mergers. However, a . . .

On the Closing Date, the certificate of incorporation and bylaws of Old Merck were amended and restated in their entirety to, among other things, rename Old Merck as "Merck Sharp & Dohme Corp." A copy of the certificate of incorporation and bylaws of Old Merck are attached hereto as Exhibits 3.1 and 3.2, respectively, and are incorporated herein by reference.

On November 3, 2009, Old Merck and Schering-Plough jointly issued a press release announcing the completion of the Mergers. A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

(d) Exhibits.

Number                                   Description

 2.1       Agreement and Plan of Merger, dated as of March 8, 2009, by and among
           Merck & Co., Inc., Schering-Plough Corporation, SP Merger Subsidiary
           One, Inc. (formerly Blue, Inc.) and SP Merger Subsidiary Two, Inc.
           (formerly Purple, Inc.) (incorporated by reference to Exhibit 2.1 to
           the Current Report on Form 8-K filed by Merck & Co., Inc. (renamed
           Merck Sharp & Dohme Corp.) on March 10, 2009).

 3.1       Restated Certificate of Incorporation of Merck & Co., Inc. (renamed
           Merck Sharp & Dohme Corp.) effective as of November 3, 2009

 3.2       Bylaws of Merck Sharp & Dohme Corp., effective as of November 3, 2009

 4.1       Indenture, dated as of November 26, 2003, between Schering-Plough
           Corporation and the Bank of New York, as Trustee (incorporated by
           reference to Exhibit 4.1 to the Current Report on Form 8-K filed by
           Schering-Plough Corporation (renamed Merck & Co., Inc.) on November 28,
           2003)

 4.2       First Supplemental Indenture, dated as of November 26, 2003, between
           Schering-Plough Corporation and The Bank of New York, as Trustee
           (incorporated by reference to Exhibit 4.2 to the Current Report on Form
           8-K filed by Schering-Plough Corporation (renamed Merck & Co., Inc.) on
           November 28, 2003)

 4.3       Second Supplemental Indenture dated as of November 26, 2003, between
           Schering-Plough Corporation and The Bank of New York, as Trustee
           (incorporated by reference to Exhibit 4.3 to the Current Report on Form
           8-K filed by Schering-Plough Corporation (renamed Merck & Co., Inc.) on
           November 28, 2003)

 4.4       Third Supplemental Indenture, dated as of September 17, 2007, between
           Schering-Plough Corporation and The Bank of New York, as Trustee
           (incorporated by reference to Exhibit 4.1 to the Current Report on Form
           8-K filed by Schering-Plough Corporation on (renamed Merck & Co., Inc.)
           September 17, 2007)

 4.5       Fourth Supplemental Indenture dated as of October 1, 2007, between
           Schering-Plough Corporation and The Bank of New York, as Trustee
           (incorporated by reference to Exhibit 4.1 to the Current Report on Form
           8-K filed by Schering-Plough Corporation (renamed Merck & Co., Inc.) on
           October 2, 2007)

 4.6       Fifth Supplemental Indenture, dated as of November 3, 2009, 2009,
           between Merck & Co., Inc., Merck Sharp & Dohme Corp. and The Bank of
           New York Mellon, as Trustee (incorporated by reference to Exhibit 4.4
           to the Current Report on Form 8-K filed by Merck & Co., Inc. on
           November 4, 2009)

 4.7       Second Supplemental Indenture, dated as of November 3, 2009, between
           Merck Sharp & Dohme Corp., Merck & Co., Inc. and U.S. Bank Trust
           National Association, as Trustee

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         (incorporated by reference to Exhibit 4.3 to the Current Report on Form
         8-K filed by Merck & Co., Inc. on November 4, 2009)

10.1     Merck Sharp & Dohme Corp. 2007 Incentive Stock Plan (incorporated by
         reference to Exhibit 10.7 to the Current Report on Form 8-K filed by
         Merck & Co., Inc. on November 4, 2009)

10.2     Merck Sharp & Dohme Corp. 2004 Incentive Stock Plan (incorporated by
         reference to Exhibit 10.8 to the Current Report on Form 8-K filed by
         Merck & Co., Inc. on November 4, 2009)

10.3     Merck Sharp & Dohme Corp. 2001 Incentive Stock Plan (incorporated by
         reference to Exhibit 10.9 to the Current Report on Form 8-K filed by
         Merck & Co., Inc. on November 4, 2009)

10.4     Merck Sharp & Dohme Corp. 1996 Inventive Stock Plan (incorporated by
         reference to Exhibit 10.10 to the Current Report on Form 8-K filed by
         Merck & Co., Inc. on November 4, 2009)

10.5     Merck & Co., Inc. 2001 Non-Employee Director Stock Option Plan
         (incorporated by reference to Exhibit 10.11 to the Current Report on Form
         8-K filed by Merck & Co., Inc. on November 4, 2009)

10.6     Merck & Co., Inc. 1996 Non-Employee Director Stock Option Plan
         (incorporated by reference to Exhibit 10.12 to the Current Report on Form
         8-K filed by Merck & Co., Inc. on November 4, 2009)

10.7     Merck & Co., Inc. Change in Control Separations Benefits Plan
         (incorporated by reference to Exhibit 10.14 to the Current Report on Form
         8-K filed by Merck & Co., Inc. on November 4, 2009)

10.8     Merck Sharp & Dohme Corp. Deferral Program, including the base Salary
         Deferral Plan (incorporated by reference to Exhibit 10.15 to the Current
         Report on Form 8-K filed by Merck & Co., Inc. on November 4, 2009)

99.1     Joint Press Release, dated November 3, 2009 (incorporated by reference to
         Exhibit 99.1 to the Current Report on Form 8-K filed by Merck & Co., Inc.
         on November 4, 2009)