SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

(Rule 13d-101)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO § 240.13d-1(a) AND AMENDMENTS THERETO FILED

PURSUANT TO § 240.13d-2(a)

Under the Securities Exchange Act of 1934

(Amendment No. 11)*

Canadian Pacific Railway Limited

(Name of Issuer)

Common Shares

(Title of Class of Securities)

13645T100

(CUSIP Number)

Roy J. Katzovicz, Esq.

Pershing Square Capital Management, L.P.

888 Seventh Avenue, 42nd Floor

New York, New York 10019

(212) 813-3700

with a copy to:

Alan J. Sinsheimer, Esq.

Sullivan & Cromwell LLP

125 Broad Street

New York, New York 10004

(212) 558-4000

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

October 24, 2013

(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 §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-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 § 240.13d-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).

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This Amendment No. 11 relates to the Schedule 13D filed on October 28, 2011 and amended on November 22, 2011, December 1, 2011, December 13, 2011, January 24, 2012, February 22, 2012, April 2, 2012, May 18, 2012, January 3, 2013, June 3, 2013 and July 30, 2013 (as so amended, the “Original 13D”), by (i) Pershing Square Capital Management, L.P., a Delaware limited partnership (“Pershing Square”); (ii) PS Management GP, LLC, a Delaware limited liability company (“PS Management”); (iii) Pershing Square GP, LLC, a Delaware limited liability company (“Pershing Square GP”); and (iv) William A. Ackman, a citizen of the United States of America (together with Pershing Square, PS Management and Pershing Square GP, the “Reporting Persons”) relating to common shares, without par value (the “Common Shares”), of Canadian Pacific Railway Limited, a corporation organized under the Canada Business Corporations Act (the “Issuer”). Capitalized terms used but not defined herein shall have the meaning set forth in the Original 13D.

Item 1. Security and Issuer.

Item 1 of the Original 13D is amended and supplemented as follows:

As of October 25, 2013, the Reporting Persons beneficially own an aggregate of 17,159,888 Common Shares (the “Subject Shares”), representing approximately 9.8% of the Common Shares outstanding.

Item 4. Purpose of the Transaction.

Item 4 of the Original 13D is amended and supplemented as follows:

The Pershing Square Funds have agreed to sell Common Shares pursuant to the Underwriting Agreement described in Item 6 below. Upon the closing of the sale of 5,965,304 Common Shares, the Pershing Square Funds will complete their previously announced intention to sell 7,000,000 Common Shares.

Item 5. Interest in the Securities of the Issuer.

Items 5(a) and (b) of the Original 13D are amended and restated as follows:

(a), (b)

Based upon the Report of Foreign Issuer on Form 6-K, filed by the Issuer on October 23, 2013, there were 175,224,565 Common Shares outstanding as of October 23, 2013.

Based on the foregoing, the Subject Shares beneficially owned by the Reporting Persons represent approximately 9.8% of the Common Shares outstanding.

Pershing Square, as the investment adviser to the Pershing Square Funds, may be deemed to have the shared power to vote or direct the vote of (and the shared power to dispose or direct the disposition of) the Subject Shares. As the general partner of Pershing Square, PS Management may be deemed to have the shared power to vote or to direct the vote of (and the shared power to dispose or direct the disposition of) the Subject Shares. As the general partner of PS and PS II, Pershing Square GP may be deemed to have the shared power to vote or to direct the vote of (and the shared power to dispose or direct the disposition of) the 5,856,578 Common Shares held for the account of PS and the 122,406 Common Shares held for the account of PS II. By virtue of William A. Ackman’s position as the Chief Executive Officer of Pershing Square and managing member of each of PS Management and Pershing Square GP, William A. Ackman may be deemed to have the shared power to vote or direct the vote of (and the shared power to dispose or direct the disposition of) the Subject Shares and, therefore, William A. Ackman may be deemed to be the beneficial owner of the Subject Shares.

As of the date hereof, none of the Reporting Persons own any Common Shares other than the Subject Shares covered in this Statement.

Item 5(c) of the Original 13D is amended and supplemented as follows:

(c)

Exhibit 99.1 to Amendment No. 11, which is incorporated by reference into this Item 5(c) as if restated in full, describes all of the transactions in Common Shares and options or other derivatives relating to Common Shares that were effected in the past 60 days.

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

Item 6 of the Original 13D is amended and supplemented as follows:

On October 24, 2013, the Pershing Square Funds entered into an underwriting agreement (the “Underwriting Agreement”) with the Issuer and Credit Suisse Securities (USA) LLC, as lead underwriter (together with the other underwriters named therein, the “Underwriters”), under which the Pershing Square Funds agreed to sell to the Underwriters 5,965,304 Common Shares, at a price of

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$139.94 per share. The sale is expected to close on October 30, 2013. The Common Shares being purchased by the Underwriters are being offered and sold pursuant to a registration statement maintained by the Issuer. In connection with the Underwriting Agreement, the Pershing Square Funds agreed to a lock-up of 90 days in respect of future sales. The foregoing description of the Underwriting Agreement does not purport to be complete and is qualified in its entirety by reference to the Underwriting Agreement, which the Reporting Persons have been advised by the Issuer will be filed by the Issuer as an exhibit to its Report of Foreign Issuer on Form 6-K, which is expected to be filed on or around October 28, 2013, and which is incorporated by reference into this Item 4 as if restated in full.

Item 7. Material to be Filed as Exhibits.

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SIGNATURES

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.

Dated: October 25, 2013

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EXHIBIT INDEX

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Exhibit 99.1

Trading Data