Under the Securities Exchange Act of 1934

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

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

(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 o.

* The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

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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Item 1.                             Security and Issuer.

The class of securities to which this statement relates is the Class A Common Shares of Seaspan Corporation (“Seaspan”), par value $0.01 per share (“Common Shares”). The address of the principal executive office of Seaspan is Unit 2, 2nd Floor, Bupa Centre, 141 Connaught Road West, Hong Kong, China.

Item 2.                             Identity and Background.

This statement is being jointly filed by the following persons (collectively, the “Reporting Persons”):

1.              V. Prem Watsa, an individual, is a citizen of Canada and is the Chairman and Chief Executive Officer of Fairfax Financial Holdings Limited. Mr. Watsa’s business address is 95 Wellington Street West, Suite 800, Toronto, Ontario M5J 2N7;

2.              The One One Zero Nine Holdco Limited (“Holdco”), a corporation incorporated under the laws of Ontario, is controlled by V. Prem Watsa. The principal business of Holdco is as an investment holding company. The principal business address and principal office address of Holdco is 95 Wellington Street West, Suite 800, Toronto, Ontario M5J 2N7;

3.              The Sixty Two Investment Company Limited (“Sixty Two”), a corporation incorporated under the laws of British Columbia, is controlled by V. Prem Watsa. The principal business of Sixty Two is as an investment holding company. The principal business address and principal office address of Sixty Two is 1600 Cathedral Place, 925 West Georgia St., Vancouver, British Columbia V6C 3L2;

4.              Fairfax Financial Holdings Limited (“Fairfax” and, together with its subsidiaries, the “Fairfax Group of Companies”), a corporation incorporated under the laws of Canada, is controlled by V. Prem Watsa. Fairfax is a holding company. The principal business address and principal office address of Fairfax is 95 Wellington Street West, Suite 800, Toronto, Ontario M5J 2N7;

5.              FFHL Group Ltd. (“FFHL”), a corporation incorporated under the laws of Canada, is a holding company. The principal business address and principal office address of FFHL is 95 Wellington Street West, Suite 800, Toronto, Ontario, Canada, M5J 2N7;

6.              Fairfax (US) Inc. (“Fairfax US”), a corporation incorporated under the laws of Delaware, is a holding company. The principal business address and principal office address of Fairfax US is 2850 Lake Vista Drive, Suite 150, Lewisville, Texas 75067;

7.              Zenith National Insurance Corp. (“ZNIC”), a corporation incorporated under the laws of Delaware, is a holding company. The principal business address and principal office address of ZNIC is 21255 Califa Street, Woodland Hills, California 91367-5021;

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8.              Zenith Insurance Company (“Zenith”), a corporation incorporated under the laws of California, is a workers’ compensation insurance company. The principal business address and principal office address of Zenith is 21255 Califa Street, Woodland Hills, California 91367-5021;

9.              Odyssey US Holdings Inc. (“Odyssey”), a corporation incorporated under the laws of Delaware, is a holding company. The principal business address and principal office address of Odyssey is 300 First Stamford Place, Stamford, Connecticut 06902;

10.       Odyssey Re Holdings Corp. (“Odyssey Re”), a corporation incorporated under the laws of Delaware, is a holding company. The principal business address and principal office address of Odyssey Re is 1209 Orange Street, Wilmington, Delaware 19801;

11.       Odyssey Reinsurance Company (“Odyssey Reinsurance”), a corporation incorporated under the laws of Connecticut, is a reinsurance company. The principal business address and principal office address of Odyssey Reinsurance is 300 First Stamford Place, Stamford, Connecticut 06902;

12.       Crum & Forster Holdings Corp. (“Crum & Forster”), a corporation incorporated under the laws of Delaware, is a holding company. The principal business address and principal office address of Crum & Forster is 305 Madison Avenue, Morristown, New Jersey 07962;

13.       United States Fire Insurance Company (“US Fire”), a corporation incorporated under the laws of Delaware, is an insurance company. The principal business address and principal office address of US Fire is 305 Madison Ave., Morristown, New Jersey 07962;

14.       RiverStone Holdings Limited (“RiverStone Holdings”), a company incorporated under the laws of the United Kingdom, is a holding company. The principal business address and principal office address of RiverStone Holdings is 161-163 Preston Road, Brighton, East Sussex, BN1 6AU, England;

15.       RiverStone Insurance Limited (“RiverStone”), a company incorporated under the laws of the United Kingdom, is an insurance and reinsurance company. The principal business address and principal office address of RiverStone is 161-163 Preston Road, Brighton, East Sussex, BN1 6AU, England;

16.       Northbridge Financial Corporation (“NFC”), a corporation incorporated under the laws of Canada, is a holding company. The principal business address and principal office address of NFC is 105 Adelaide Street West, 7th Floor, Toronto, Ontario M5H 1P9;

17.       Northbridge General Insurance Corporation (“Northbridge General”), a corporation incorporated under the laws of Canada, is a property/casualty insurance company. The principal business address and principal office address of Northbridge General is 105 Adelaide Street West, 7th Floor, Toronto, Ontario M5H 1P9;

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18.       1102952 B.C. Unlimited Liability Company (“1102952”), a corporation incorporated under the laws of British Columbia, is a holding company. The principal business address and principal office address of 1102952 is 1600-925 West Georgia Street, Vancouver, British Columbia, V6C 3L2;

19.       Fairfax Financial Holdings (Switzerland) GmbH (“FFHS”), a corporation incorporated under the laws of Switzerland, is a holding company. The principal business address and principal office address of FFHS is Gubelstrasse 24, 6300, Zug, Switzerland;

20.       Allied World Assurance Company Holdings, GmbH (“Allied Holdings GmbH”), a limited liability company incorporated under the laws of Switzerland, is a holding company. The principal business address and principal office address of Allied Holdings GmbH is Park Tower, 15th Floor, Gubelstrasse 24, 6300, Zug, Switzerland;

21.       Allied World Assurance Company Holdings, Ltd (“Allied Holdings Ltd”), a corporation incorporated under the laws of Bermuda, is a holding company. The principal business address and principal office address of Allied Holdings Ltd is 27 Richmond Road, Pembroke HM 08, Bermuda; and

22.       Allied World Assurance Company, Ltd (“Allied Assurance”), a corporation incorporated under the laws of Bermuda, is an insurance company. The principal business address and principal office address of Allied Assurance is 27 Richmond Road, Pembroke HM 08, Bermuda.

Neither the filing of this Schedule 13D nor the information contained herein shall be deemed to constitute an affirmation by V. Prem Watsa, Holdco, Sixty Two, Fairfax, FFHL, Fairfax US, ZNIC, Zenith, Odyssey, Odyssey Re, Odyssey Reinsurance, Crum & Forster, US Fire, RiverStone Holdings, RiverStone, NFC, Northbridge General, 1102952, FFHS, Allied Holdings GmbH, Allied Holdings Ltd, or Allied Assurance that it is the beneficial owner of the Common Shares referred to herein for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or for any other purpose, and such beneficial ownership is expressly disclaimed.

The name, present principal occupation or employment and name, principal business and address of any corporation or other organization in which such employment is conducted and the citizenship of each director and executive officer of each of the Reporting Persons is set forth in Annex A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T and U as the case may be, and such Annexes are incorporated herein by reference.

Pursuant to Rule 13d-1(k) under the Exchange Act, the Reporting Persons have agreed to file jointly one statement with respect to their ownership of the Common Shares.

During the last five years, none of the Reporting Persons, and to the best of each such Reporting Person’s knowledge, none of the executive officers or directors of such Reporting Person have been (a) convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or (b) a party to a civil proceeding of a judicial or administrative body of

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competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

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

The source of funds for the purchase of the Warrants (as defined herein), which are exercisable for the Common Shares beneficially owned by the Reporting Persons, was cash on hand from existing investment portfolios.

Item 4.                             Purpose of Transaction.

The Reporting Persons acquired the Warrants, which are exercisable for Common Shares, for investment purposes. One or more entities within the Fairfax Group of Companies, including one or more of the Reporting Persons, may determine to purchase additional securities of Seaspan in the open market or otherwise, depending upon price, market conditions, availability of funds, evaluation of alternative investments and other factors. While none of the Reporting Persons has any present plans to sell any Warrants, Common Shares or other securities of Seaspan, one or more of them could determine, based upon the same set of factors listed above with respect to purchases, to sell some or all of such securities. The Reporting Persons have no intention to effect any of the transactions specified in Item 4 of Schedule 13D.

Item 5.                             Interest in Securities of the Issuer.

(a)         Based on the most recent information available, the aggregate number and percentage of Common Shares (the securities identified pursuant to Item 1 of this Schedule 13D) that are beneficially owned by each of the Reporting Persons is set forth in boxes 11 and 13 of the second part of the cover page to this Schedule 13D for each of the Reporting Persons, and such information is incorporated herein by reference.

(b)         Except as described below, the numbers of Common Shares as to which each of the Reporting Persons has sole voting power, shared voting power, sole dispositive power and shared dispositive power is set forth in boxes 7, 8, 9 and 10, respectively, on the second part of the cover page to this Schedule 13D for each of the Reporting Persons, and such information is incorporated herein by reference.

(c)          Except as described herein, none of the Reporting Persons, nor, to the best knowledge of the Reporting Persons, any person listed in Annex A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T and U beneficially owns, or has acquired or disposed of, any Common Shares during the last 60 days.

(d)         No person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of Common Shares held by the Reporting Persons other than each of the Reporting Persons.

(e)          Not applicable.

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

On January 17, 2018 and on February 14, 2018, Seaspan entered into a series of agreements as described in the Report of Foreign Private Issuer on Form 6-K filed by Seaspan on February 14, 2018  (the “Form 6-K”, with capitalized terms used below not defined herein having the meanings ascribed to them in the Form 6-K), in connection with certain financing transactions. Pursuant to these transactions, Seaspan issued to certain of the Reporting Persons warrants (the “Warrants”) representing the right to purchase an aggregate 38,461,539 Common Shares.

On January 17, 2018, Seaspan entered into a subscription agreement (the “Subscription Agreement”) by and between Seaspan and Hamblin Watsa Investment Counsel Ltd., investment manager for certain of the Reporting Persons (the “Purchasers”), pursuant to which Seaspan issued for cash to the Purchasers $250.0 million in aggregate principal amount of 5.50% Senior Notes due 2025 (the “Notes”) and the Warrants to purchase 38,461,539 Common Shares in a private placement exempt from the registration requirements of the Securities Act of 1933, as amended.

Each of the Warrants has an exercise term of 7 years from February 14, 2018 and may be exercised by each holder thereof by cash at an exercise price of $6.50 (subject to adjustments provided in the Warrant Agreement) per Common Share or, if such holder is also a holder of Notes, offsetting the Warrant exercise price against the outstanding principal balance of such Notes, or a combination thereof. At any time after February 14, 2022, Seaspan may require all holders of Warrants to exercise their Warrants, in whole or in part, if the fair market value of a Common Share, as determined in accordance with the Warrant Agreement, equals or exceeds two times the exercise price on the third trading day prior to the date on which Seaspan delivers notice of the required exercise.

In addition, the Warrants are subject to customary anti-dilution adjustments in the event of splits or combinations of Common Shares; distributions on Common Shares paid in Common Shares, other securities, property or rights; dividends in excess of the current quarterly rate; a Company tender or exchange offer; issuances of Common Shares (or securities convertible into or exchangeable for Common Shares) in non-public offerings at a per Common Share price below a specified discount to the then Common Share fair market value and other similar events.

Simultaneously with the closing of the refinancing transactions, Seaspan, certain subsidiary guarantors of Seaspan (the “Guarantors”) and the Purchasers entered into a registration rights agreement (the “Registration Rights Agreement”) pursuant to which Seaspan agreed, upon certain terms and conditions, to (a) on or prior to 180 days after February 14, 2018, complete an offer to the holders of the Notes to exchange any and all of the Notes and the Guarantees for a like aggregate principal amount of debt securities issued by Seaspan and guaranteed by the Guarantors, which debt securities and guarantees are substantially identical to the Notes and the Guarantees, except that they have been registered pursuant to an effective registration statement under the Securities Act, and (b) on or prior to 60 days after February 14,

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2018, to file a registration statement covering the resale of the Common Shares issuable upon the exercise of the Warrants. In addition, the Registration Rights Agreement provides certain incidental “piggy-back” registration rights, which generally allow the holders of the Warrants to participate in registered offerings of Seaspan’s Common Shares that are initiated by Seaspan or on behalf of other holders of Seaspan’s securities, as well as demand rights, which allow holders of the Warrants to demand that Seaspan register the Common Shares issuable upon the exercise of the Warrants in an underwritten offering.

The foregoing descriptions of the Subscription Agreement, the Warrants and the Registration Rights Agreement do not purport to be complete and are qualified in their entirety by reference to the Subscription Agreement, Warrant Agreement and the Registration Rights Agreement. Copies of the Warrant Agreement and the Registration Rights Agreement are filed as Exhibits 4.3 and 4.4, respectively, to the Form 6-K and are incorporated by reference herein.

Item 7.                             Material to be Filed as Exhibits.

The following is filed herewith as an exhibit:

Ex. 1:                                                                Members of filing group

Ex. 2:                                                                Joint filing agreement dated as of February 26, 2018 among V. Prem Watsa, The One One Zero Nine Holdco Limited, The Sixty Two Investment Company Limited, Fairfax Financial Holdings Limited, FFHL Group Ltd., RiverStone Holdings Limited, RiverStone Insurance Limited, Fairfax (US) Inc., Zenith National Insurance Corp., Zenith Insurance Company, Odyssey US Holdings Inc., Odyssey Re Holdings Corp., Odyssey Reinsurance Company, Crum & Forster Holdings Corp., United States Fire Insurance Company, RiverStone Holdings Limited, RiverStone Insurance Limited, Northbridge Financial Corporation, Northbridge General Insurance Corporation, 1102952 B.C. Unlimited Liability Company, Fairfax Financial Holdings (Switzerland) GmbH, Allied World Assurance Company Holdings, GmbH, Allied World Assurance Company Holdings, Ltd and Allied World Assurance Company, Ltd

Ex. 3:                                                                Power of attorney, dated February 9, 2017

Ex. 4:                                                                Power of attorney, dated February 26, 2018

Ex. 5:                                                                Warrant Agreement, dated February 14, 2018, by and among Seaspan Corporation and the investors specified therein (incorporated by reference to Exhibit 4.3 of the Form 6-K)

Ex. 6:                                                                Registration Rights Agreement, dated February 14, 2018, by and among Seaspan Corporation, the subsidiary Guarantors and the investors specified therein (incorporated by reference to Exhibit 4.4 of the Form 6-K)

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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

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SIGNATURE

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