ESGR Enstar Group Ltd

Explanatory Note

This Amendment No. 4 to Schedule 13D (this “ Amendment ”) amends and supplements the Schedule 13D originally filed with the United States Securities and Exchange Commission (the “ SEC ”) on June 3, 2015, as amended on August 28, 2015, March 4, 2016 and May 16, 2016 (together, the “ Statement ”). This Amendment is being filed on behalf of Canada Pension Plan Investment Board (“ CPPIB ”), CPPIB Epsilon Ontario Limited Partnership (the “ Partnership ”), the CPPIB Epsilon Ontario Trust (the “ Trust ”) and Poul Winslow (together, the “ Reporting Persons ”) identified on the cover pages of this Amendment.

Item 4. Purpose of the Transaction

Item 4 is amended and restated in its entirety as follows:

The acquisition of Ordinary Shares by CPPIB was undertaken for investment purposes. CPPIB has voting rights with respect to its Ordinary Shares. CPPIB also has a right to nominate a representative of CPPIB to the Board of Directors of the Issuer (the “ Board ”) (pursuant to the Shareholder Rights Agreement, as defined and described in Item 4(d) below).

The following describes plans or proposals that the Reporting Persons may have with respect to the matters set forth in Item 4(a)-(j) of Schedule 13D:

(a) On September 15, 2016, CPPIB entered into the Purchase and Sale Agreement (the “ PSA ”), by and among CPPIB, GSCP VI AIV Navi, Ltd., GSCP VI Offshore Navi, Ltd., GSCP VI Parallel AIV Navi, Ltd., GSCP VI Employee Navi Ltd. and GSCP VI GmbH Navi, L.P. (together, the “ GS Entities ”), pursuant to which CPPIB agreed to purchase an aggregate of 1,192,941 Series C non-voting convertible ordinary shares, par value US$1.00 per share, of the Issuer for an aggregate purchase price of $189,081,148.50.

References to and descriptions of the PSA are qualified in their entirety by the terms of the PSA, a copy of which is attached hereto as Exhibit 99.1 and is incorporated in its entirety into this Item 4(a).

(b) None.

(c) None.

(d) Pursuant to Section 2.01 of the Shareholder Rights Agreement, dated as of June 3, 2015, by and between the Issuer and CPPIB (the “ Shareholder Rights Agreement ”), CPPIB has the right to nominate for appointment or as a candidate for election one representative to the Issuer’s Board of Directors (the “ CPPIB Director Nominee ”). The Issuer has agreed, pursuant to Section 2.01 of the Shareholder Rights Agreement, to use its commercially reasonable efforts to put forward such CPPIB Director Nominee for election at future applicable annual meetings or take such other steps as are required to have such CPPIB Director Nominee elected or appointed to the Board. This designation right terminates if CPPIB ceases to beneficially own at least 75% of the total number of Ordinary Shares and non-voting preferred shares it acquired under the Securities Purchase Agreement (as defined in the Schedule 13D filed on June 3, 2015).

References to, and descriptions of, the Shareholder Rights Agreement as set forth in this Item 4(d) are qualified in their entirety by the terms of the Shareholder Rights Agreement, a copy of which is filed herewith as Exhibit 99.2 , incorporated by reference to the Form 8-K filed by the Issuer (File No. 001-33289) with the Securities and Exchange Commission on June 3, 2015, and which is incorporated in its entirety in this Item 4(d).

(e) None.

(f) None.

(g) None.

(h) None.

(i) None.

(j) None.

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

Item 6 is hereby amended and supplemented by adding the following:

The information provided or incorporated by reference in Item 4(a) is hereby incorporated by reference herein.

GS Registration Rights Agreement and GS Registration Rights Assignment

The Issuer and the GS Entities are parties to a Registration Rights Agreement, dated April 20, 2011 (the “ GS Registration Rights Agreement ”), which provides the GS Entities with certain rights to cause shares of the Issuer to be registered under the Securities Act of 1933, as amended (the “ Securities Act ”), in accordance with the terms and conditions of the GS Registration Rights Agreement. The GS Entities are entitled to make two written requests for the Company to register under the Securities Act all or any part of certain securities owned by them, subject to certain exceptions and conditions set forth in the GS Registration Rights Agreement. References to, and descriptions of, the GS Registration Rights Agreement as set forth in this Item 6 are qualified in their entirety by the terms of the GS Registration Rights Agreement, a copy of which is filed herewith as Exhibit 99.3 , incorporated by reference to the Form 8-K filed by the Issuer (File No. 001-33289) with the Securities and Exchange Commission on April 20, 2011, and which is incorporated in its entirety in this Item 6.

Pursuant to the PSA, CPPIB and the GS Entities executed an Assignment of Registration Rights, dated September 15, 2016 (the “ GS Registration Rights Assignment ”), which is subject to the consent of the Issuer. The GS Registration Rights Assignment provides for an assignment to CPPIB of the GS Entities’ rights under the GS Registration Rights Agreement related to the securities transferred pursuant to the PSA (including one of the GS Entities’ two demand registration rights). References to, and descriptions of, the GS Registration Rights Assignment as set forth in this Item 6 are qualified in their entirety by the terms of the GS Registration Rights Assignment, a copy of which is attached hereto as Exhibit 99.4 and is incorporated in its entirety in this Item 6.

Item 7. Material to be Filed as Exhibits

SIGNATURE

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.

ATTENTION

Intentional misstatements or omissions of fact constitute Federal Criminal Violations (See 18 U.S.C. 1001)

[ Signature Page to Schedule 13D Amendment ]

SIGNATURE

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.

ATTENTION

Intentional misstatements or omissions of fact constitute Federal Criminal Violations (See 18 U.S.C. 1001).

[ Signature Page to Schedule 13D Amendment ]

SIGNATURE

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.

ATTENTION

Intentional misstatements or omissions of fact constitute Federal Criminal Violations (See 18 U.S.C. 1001).

[ Signature Page to Schedule 13D Amendment ]

SIGNATURE

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.

ATTENTION

Intentional misstatements or omissions of fact constitute Federal Criminal Violations (See 18 U.S.C. 1001)

[ Signature Page to Schedule 13D Amendment ]