UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

(Rule 13d-101)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO RULE 13d-1(a) AND AMENDMENTS THERETO FILED

PURSUANT TO RULE 13d-2(a)

Under the Securities Exchange Act of 1934

(Amendment No. 6)*

VALEANT PHARMACEUTICALS INTERNATIONAL, INC.

(Name of Issuer)

Common Stock

(Title of Class of Securities)

91911K102

(CUSIP Number)

Steve Fraidin

Steve Milankov

Pershing Square Capital Management, L.P.

888 Seventh Avenue, 42nd Floor

New York, New York 10019

212-813-3700

With a Copy to:

Richard M. Brand

Cadwalader, Wickersham & Taft LLP

One World Financial Center

New York, NY 10281

212-504-5757

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

March 22, 2016

(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 Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box.  ¨

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other parties to whom copies are to be sent.

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).

13D

13D

13D

This Amendment No. 6 to Schedule 13D (this “Amendment No. 6”) amends and supplements the statement on Schedule 13D (the “Original Schedule 13D”), filed on March 25, 2015 (the Original Schedule 13D, as amended and supplemented through the date of this Amendment No. 6, the “Schedule 13D”), by Pershing Square Capital Management, L.P., a Delaware limited partnership (“Pershing Square”); PS Management GP, LLC, a Delaware limited liability company (“PS Management”); and William A. Ackman, a citizen of the United States of America (together with Pershing Square and PS Management, the “Reporting Persons”), relating to the common stock, no par value (the “Common Stock”), of Valeant Pharmaceuticals International, Inc., a corporation continued under the laws of British Columbia, Canada (the “Issuer”). Capitalized terms used but not defined in this amendment shall have the meanings set forth in the Schedule 13D.

Except as specifically amended by this Amendment No. 6, the Schedule 13D is unchanged.

Item 6 of the Schedule 13D is hereby amended and supplemented to add the following information:

In connection with Mr. Ackman’s appointment to the Issuer’s Board on March 21, 2016, the Issuer entered into an information sharing agreement with Pershing Square, on behalf of itself and the Pershing Square Funds, and Mr. Ackman that is filed as Exhibit 99.10. That agreement is incorporated by reference into this Item 6 as if restated in full herein.

Item 7 of Schedule 13D is hereby amended and supplemented to add the following exhibit:

SIGNATURES

After reasonable inquiry and to the best of each of the undersigned’s knowledge and belief, each of the undersigned certify that the information set forth in this statement is true, complete and correct.

EXHIBIT INDEX

Exhibit 99.10

		PERSHING SQUARE CAPITAL MANAGEMENT, L.P.			888 SEVENTH AVENUE, 42ND FLOOR NEW YORK, NY 10019 P: 212-813-3700 F: 212-286-1133

March 22, 2016

Valeant Pharmaceuticals International, Inc.

2150 St. Elzéar Blvd. West

Laval, Quebec

Canada, H7L 4A8

Attention: J. Michael Pearson

Dear Mr. Pearson:

I am delighted to join the Valeant Pharmaceuticals International, Inc. (“Valeant”) board, and I look forward to making a contribution to the company.

This letter, intended solely for the benefit of Valeant, contains a series of undertakings by myself, my firm and the investment funds that we advise (collectively, “Pershing Square” or “we”). The undertakings in the following two paragraphs of this letter will be effective so long as the confidential information shared with me as a Valeant director or shared with Pershing Square (by me or by Valeant) remains non-public, and the undertakings in the penultimate paragraph of this letter will be effective while I am a Valeant director. All such undertakings are intended to be legally binding on Pershing Square and to address various issues that we have discussed.

We are sensitive to Valeant’s concerns regarding confidentiality and other regulatory issues, and feel that it would be appropriate to restrict ourselves as set forth in this letter in order to address those considerations. To that end, I hereby undertake, consistent with my fiduciary duties and confidentiality obligations as a Valeant director, to refrain from communicating to anyone (whether to any company in which we have an investment or otherwise) confidential information I learn in my capacity as a director of Valeant; provided that I may communicate such information to members of my firm, Pershing Square, Cadwalader, Wickersham & Taft LLP and our other outside advisors, in each case, who need to know such information for the purpose of advising Pershing Square on its investment in Valeant; provided, further, that Pershing Square shall be (and shall cause such persons to be) bound by the same confidentiality restrictions that are otherwise applicable to me. In addition, this letter memorializes that, except as required by applicable law pursuant to the next sentence, all of Pershing Square’s personnel have agreed to maintain the confidentiality of Valeant’s nonpublic information they obtain directly from Valeant or through my service on the Valeant board. In the event that a recipient

Valeant Pharmaceuticals International, Inc.

March 22, 2016

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of such information is required by any court, governmental or regulatory authority, or by legal process to disclose any such information, Pershing Square shall promptly notify Valeant of such requirement and cooperate with Valeant in its efforts to limit any such disclosure prior thereto; provided, that if disclosure is nonetheless legally required, the recipient may disclose such portion of the information as counsel has advised is legally required or advisable to be produced. Pershing Square (i) acknowledges that applicable United States and Canadian securities laws prohibit any person who has material nonpublic information about a company from purchasing or selling securities of such company or from communicating such information to any other person under circumstances in which it is reasonably foreseeable that such person is likely to purchase or sell such securities and (ii) agrees to comply with (and to cause Pershing Square personnel to comply with) the United States and Canadian securities laws in respect of communicating any such information and refraining from trading in Valeant securities while in possession of such information in violation of such securities laws.

Furthermore, we agree that, in connection with my service on the Valeant board, I will comply with the policies (as applied to me on a reasonable and good faith basis) applicable generally to directors of Valeant as currently in effect (together with changes to such policies imposed on a reasonable and good faith basis), and except as otherwise agreed between Pershing Square and Valeant, Pershing Square and its controlled affiliates will not engage in the purchase or sale of Valeant securities during Valeant blackout periods under the restriction calendar currently in effect, together with changes to such calendar or unscheduled blackout periods (in either case imposed on a reasonable and good faith basis). Valeant shall not be responsible for compliance by Pershing Square or me with the securities laws, including regulations relating to insider trading.

I look forward to working together with you and the board.

Valeant Pharmaceuticals International, Inc.

March 22, 2016

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