As filed with the Securities and Exchange Commission on November 10, 2025

Registration No. 333-289276

UNITED STATES 

SECURITIES AND EXCHANGE COMMISSION 

Washington, D.C. 20549

POST-EFFECTIVE AMENDMENT NO. 1 

to 

FORM S-4 

REGISTRATION STATEMENT

UNDER 

THE SECURITIES ACT OF 1933 

(Address, including ZIP code, and telephone number, including area code, of registrant’s principal
executive offices)

Jeanette Miller 

Senior Vice President and Chief Legal Officer 

1414 Raleigh Road, Suite 405 

Chapel Hill, North Carolina 27517 

Telephone: (919) 900-1200 

(Name, address, including ZIP code, and telephone number, including area code, of agent for service)

With copies to: 

Eric T. Juergens
Debevoise & Plimpton LLP 

66 Hudson Boulevard
New York, New York 10001 

(212) 909-6000

Approximate date of commencement of proposed sale of the securities to the public: Not applicable.

If the securities being registered on this form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, please check the following box. ¨

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act of 1933, as amended (the “Securities Act”), check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨

If this form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). (Check one)

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ¨

If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction: Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer) ¨

Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer) ¨

The registration statement shall hereafter become effective in accordance with the provisions of Section 8(a) of the Securities Act.

EXPLANATORY NOTE

This Post-Effective Amendment No. 1 (this “Amendment”) to Registration Statement No. 333-289276 (the “Registration Statement”) is being filed pursuant to Rule 414(d) under the Securities Act of 1933, as amended (the “Securities Act”), by James River Group Holdings, Inc., a Delaware corporation (the “Company”), as the successor to James River Group Holdings, Ltd., a Bermuda exempted company. Effective November 7, 2025, James River Group Holdings, Ltd. changed its jurisdiction of incorporation from Bermuda to the State of Delaware (the “Domestication”) and changed its legal name to James River Group Holdings, Inc. The Company expressly adopts the Registration Statement, as modified by this Amendment, as its own registration statement for all purposes of the Securities Act and the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

For the purposes of this Amendment and the Registration Statement, references to the “Company,” “James River,” the “Registrant,” “we,” “our,” “us” and similar terms mean, as of any time prior to the Domestication, James River Group Holdings, Ltd. and, as of any time after the Domestication, James River Group Holdings, Inc. The information contained in this Amendment sets forth additional information to reflect the Domestication. All documents filed by the Company under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act before the effective date of the Domestication will not reflect the change in our name, jurisdiction of incorporation or capital structure.

The Domestication was effected in the manner described in the section of the Registration Statement entitled “The Domestication.” In the Domestication, James River Group Holdings, Ltd. discontinued its existence as a Bermuda exempted company as provided under Sections 132G and 132H of The Companies Act 1981 of Bermuda and, pursuant to Section 388 of the General Corporation Law of the State of Delaware (the “DGCL”), continued its existence under the DGCL as a corporation incorporated in the State of Delaware. Our consolidated business, operations, assets and liabilities, as well as our principal locations (other than our registered office in Bermuda) and fiscal year, are the same immediately after the Domestication as they were immediately prior to the Domestication. In addition, the directors and executive officers of the Company immediately after the Domestication are the same individuals who were directors and executive officers, respectively, of James River Group Holdings, Ltd. immediately prior to the Domestication.

The Company’s common stock continues to be listed for trading on the Nasdaq Global Select Market under the ticker symbol “JRVR.” Upon effectiveness of the Domestication, the Company’s CUSIP number relating to its common stock changed to 46990A 102.

In connection with the Domestication, common shares of James River Group Holdings, Ltd., par value $0.0002 per share (the “common shares”) (including fractions of common shares, as the case may be), issued and outstanding immediately prior to the effective time of the Domestication automatically converted by operation of law into an equivalent number of shares of common stock, par value $0.0002 per share (the “common stock”) (or fractions of shares of common stock, as the case may be), of James River Group Holdings, Inc. The number of shares of common stock of the Company outstanding immediately after the Domestication is the same as the number of common shares of James River Group Holdings, Ltd. outstanding immediately prior to the Domestication. Consequently, each holder of a common share (or fraction thereof) of James River Group Holdings, Ltd. immediately prior to the Domestication held, immediately thereafter, a share of common stock (or fraction thereof) of the Company representing the same proportional equity interest in the Company as that shareholder held in James River Group Holdings, Ltd. and representing the same class of shares.

The rights of holders of the Company’s common stock are now governed by the Company’s Delaware certificate of incorporation, its Delaware by-laws and the DGCL, each of which is described in James River Group Holdings, Ltd.’s final prospectus relating to the Domestication, which was filed with the Securities and Exchange Commission (“Commission”) pursuant to Rule 424(b)(3) on August 19, 2025 (the “Final Prospectus”). The Final Prospectus is part of the Registration Statement.

PART II 

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 20. Indemnification of Officers and Directors

Section 102(b)(7) of the DGCL allows a corporation to provide in its certificate of incorporation that a director or officer of the corporation will not be personally liable to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director or officer, except (1) for any breach of the director’s or officer’s duty of loyalty to the corporation or its stockholders, (2) for acts or omissions by a director or officer not in good faith or which involve intentional misconduct or a knowing violation of law, (3) for payments of unlawful dividends or unlawful stock repurchases or redemptions made to a director, (4) for any transaction from which the director or officer derived an improper personal benefit or (5) an officer in any action by or in the right of the corporation.

Section 145(a) of the DGCL provides, in general, that a corporation may indemnify any person who was or is a party to or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation), because he or she is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with such action, suit or proceeding, if he or she acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the corporation and, with respect to any criminal action or proceeding, had no reasonable cause to believe his or her conduct was unlawful.

Section 145(b) of the DGCL provides, in general, that a corporation may indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor because the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys’ fees) actually and reasonably incurred by the person in connection with the defense or settlement of such action or suit if he or she acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the corporation, except that no indemnification will be made with respect to any claim, issue or matter as to which he or she will have been adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery or other adjudicating court determines that, despite the adjudication of liability but in view of all of the circumstances of the case, he or she is fairly and reasonably entitled to indemnity for such expenses that the Court of Chancery or other adjudicating court will deem proper.

Section 145(g) of the DGCL provides, in general, that a corporation may purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against any liability asserted against such person and incurred by such person in any such capacity, or arising out of his or her status as such, whether or not the corporation would have the power to indemnify the person against such liability under Section 145 of the DGCL.

Our certificate of incorporation provides that no director or officer of James River Group Holdings, Inc. shall be liable to the Company or its stockholders for monetary damages for breach of fiduciary duty as a director or officer (including with regard to any actions taken or omitted as a director or officer of James River Group Holdings, Ltd., whether taken or omitted prior to the effective time of the Domestication, in connection with the discontinuance of James River Group Holdings, Ltd. in Bermuda or the continuance of James River Group Holdings, Ltd. in the State of Delaware or otherwise) except to the extent that such exemption from liability or limitation thereof is not permitted under the DGCL as currently in effect or as the same may be amended. This provision in the certificate of incorporation does not eliminate the directors’ or officers’ fiduciary duty, and in appropriate circumstances, equitable remedies such as injunctive or other forms of non-monetary relief will remain available under Delaware law. In addition, each director or officer will be subject to liability for breach of the director’s or officer’s duty of loyalty to the Company or its stockholders, for acts or omissions not in good faith or involving intentional misconduct, for knowing violations of law, for actions leading to improper personal benefit to the director or officer, and, with respect to directors only, for payment of dividends or approval of stock repurchases or redemptions that are unlawful under Delaware law. The provision also does not affect a director’s or officer’s responsibilities under any other law, such as the federal securities laws or state or federal environmental laws.

The Company’s by-laws also provide that James River Group Holdings, Inc. shall indemnify and hold harmless to the fullest extent permitted by law any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative, formal or informal, including all appeals by reason of the fact that (x) such person is or was serving or has agreed to serve as a director or officer of James River Group Holdings, Inc., or (y) such person, while serving as a director or officer of James River Group Holdings, Inc., is or was serving or has agreed to serve at the request of James River Group Holdings, Inc. as a director, officer, employee, manager or agent of another corporation, partnership, joint venture, trust or other enterprise or (z) such person is or was serving or has agreed to serve at the request of James River Group Holdings, Inc. as a director, officer or manager of another corporation, partnership, joint venture, trust or other enterprise, or by reason of any action alleged to have been taken or omitted by such person in such capacity, and who satisfies the applicable standard of conduct set forth in the DGCL or other applicable law. For purposes of the indemnification described in this paragraph, references to James River Group Holdings, Inc. include James River Group Holdings, Ltd. as incorporated under Bermuda law prior to the continuance of its existence under Delaware law as James River Group Holdings, Inc. James River Group Holdings, Inc. will remain obligated on any indemnification obligations of James River Group Holdings, Ltd. arising prior to the Domestication.

We maintain directors’ and officers’ insurance policies that cover our directors and officers.

Subject to limitations imposed by Delaware law, the Company may enter into agreements that provide indemnification to the directors, officers and other persons serving at our request as a director, officer, employee or agent of another enterprise for all actions, liabilities, losses, damages or expenses incurred or suffered by the indemnified person arising out of such person’s service in such capacity.

Item 21. Exhibits and Financial Statement Schedules

(a)  Exhibits. The following exhibits are filed as part of this Registration Statement:

Item 22. Undertakings

The undersigned registrant hereby undertakes:

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the Registrant has duly caused this Post-Effective Amendment No. 1 to the Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Chapel Hill, State of North Carolina, on the 10th day of November, 2025.