# EDGAR Filing Document

**Accession Number:** 0001565854
**File Stem:** 0002063407-25-000077
**Filing Date:** 2025-11
**Character Count:** 14118
**Document Hash:** 81b38c99e77254baff2dfdce8be234b6
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0002063407-25-000077.hdr.sgml**: 20251112

**ACCESSION NUMBER**: 0002063407-25-000077

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13G/A

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20251112

**DATE AS OF CHANGE**: 20251112

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** James River Group Holdings, Inc.
- **CENTRAL INDEX KEY:** 0001620459
- **STANDARD INDUSTRIAL CLASSIFICATION:** FIRE, MARINE & CASUALTY INSURANCE [6331]
- **ORGANIZATION NAME:** 02 Finance
- **EIN:** 980585280
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13G/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-88455
- **FILM NUMBER:** 251471046

**BUSINESS ADDRESS:**
- **STREET 1:** 1414 RALEIGH ROAD, SUITE 405
- **CITY:** CHAPEL HILL
- **STATE:** NC
- **ZIP:** 27517
- **BUSINESS PHONE:** 919-900-1200

**MAIL ADDRESS:**
- **STREET 1:** 1414 RALEIGH ROAD, SUITE 405
- **CITY:** CHAPEL HILL
- **STATE:** NC
- **ZIP:** 27517

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** James River Group Holdings, Ltd.
- **DATE OF NAME CHANGE:** 20140924
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Zimmer Partners, LP
- **CENTRAL INDEX KEY:** 0001565854

**ORGANIZATION NAME:**
- **EIN:** 900883937
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13G/A

**BUSINESS ADDRESS:**
- **STREET 1:** 9 WEST 57TH STREET
- **STREET 2:** 33RD FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10019
- **BUSINESS PHONE:** 212.440.0770

**MAIL ADDRESS:**
- **STREET 1:** 9 WEST 57TH STREET
- **STREET 2:** 33RD FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10019

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## SCHEDULE 13G

### Under the Securities Exchange Act of 1934

**(Amendment No. 1)**

**Issuer:** James River Group Holdings, Ltd.

**Title of Class of Securities:** Common Shares, par value $0.0002 per share

**CUSIP Number:** G5005R107

**Date of Event Which Requires Filing of this Statement:** 09/30/2025

**Check the appropriate box to designate the rule pursuant to which this Schedule is filed:**

- [x] Rule 13d-1(b)

- [ ] Rule 13d-1(c)

- [ ] Rule 13d-1(d)

---

| 1. | Names of Reporting Persons<br>Zimmer Partners, LP | Names of Reporting Persons<br>Zimmer Partners, LP |
|:---|:---|:---|:---|
| 2. | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] |
| 3. | SEC Use Only | SEC Use Only |
| 4. | Citizenship or Place of Organization<br>DE | Citizenship or Place of Organization<br>DE |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 5. | Sole Voting Power<br>0 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 6. | Shared Voting Power<br>4591638 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 7. | Sole Dispositive Power<br>0 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 8. | Shared Dispositive Power<br>4591638 |
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person<br>4591638 | Aggregate Amount Beneficially Owned by Each Reporting Person<br>4591638 |
| 10. | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] |
| 11. | Percent of Class Represented by Amount in Row (9)<br>10% | Percent of Class Represented by Amount in Row (9)<br>10% |
| 12. | Type of Reporting Person (See Instructions)<br>IN, HC | Type of Reporting Person (See Instructions)<br>IN, HC |

---

| 1. | Names of Reporting Persons<br>Zimmer Financial Services Group LLC | Names of Reporting Persons<br>Zimmer Financial Services Group LLC |
|:---|:---|:---|:---|
| 2. | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] |
| 3. | SEC Use Only | SEC Use Only |
| 4. | Citizenship or Place of Organization<br>DE | Citizenship or Place of Organization<br>DE |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 5. | Sole Voting Power<br>0 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 6. | Shared Voting Power<br>4591638 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 7. | Sole Dispositive Power<br>0 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 8. | Shared Dispositive Power<br>4591638 |
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person<br>4591638 | Aggregate Amount Beneficially Owned by Each Reporting Person<br>4591638 |
| 10. | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] |
| 11. | Percent of Class Represented by Amount in Row (9)<br>10% | Percent of Class Represented by Amount in Row (9)<br>10% |
| 12. | Type of Reporting Person (See Instructions)<br>OO, HC | Type of Reporting Person (See Instructions)<br>OO, HC |

---

| 1. | Names of Reporting Persons<br>Zimmer Partners GP, LLC | Names of Reporting Persons<br>Zimmer Partners GP, LLC |
|:---|:---|:---|:---|
| 2. | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] |
| 3. | SEC Use Only | SEC Use Only |
| 4. | Citizenship or Place of Organization<br>DE | Citizenship or Place of Organization<br>DE |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 5. | Sole Voting Power<br>0 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 6. | Shared Voting Power<br>4591638 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 7. | Sole Dispositive Power<br>0 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 8. | Shared Dispositive Power<br>4591638 |
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person<br>4591638 | Aggregate Amount Beneficially Owned by Each Reporting Person<br>4591638 |
| 10. | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] |
| 11. | Percent of Class Represented by Amount in Row (9)<br>10% | Percent of Class Represented by Amount in Row (9)<br>10% |
| 12. | Type of Reporting Person (See Instructions)<br>OO, HC | Type of Reporting Person (See Instructions)<br>OO, HC |

---

| 1. | Names of Reporting Persons<br>Stuart J. Zimmer | Names of Reporting Persons<br>Stuart J. Zimmer |
|:---|:---|:---|:---|
| 2. | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] | Check the Appropriate Box if a Member of a Group (See Instructions)<br>(a) [ ] (b) [ ] |
| 3. | SEC Use Only | SEC Use Only |
| 4. | Citizenship or Place of Organization<br>X1 | Citizenship or Place of Organization<br>X1 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 5. | Sole Voting Power<br>0 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 6. | Shared Voting Power<br>4591638 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 7. | Sole Dispositive Power<br>0 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 8. | Shared Dispositive Power<br>4591638 |
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person<br>4591638 | Aggregate Amount Beneficially Owned by Each Reporting Person<br>4591638 |
| 10. | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] | Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) [ ] |
| 11. | Percent of Class Represented by Amount in Row (9)<br>10% | Percent of Class Represented by Amount in Row (9)<br>10% |
| 12. | Type of Reporting Person (See Instructions)<br>IN, HC | Type of Reporting Person (See Instructions)<br>IN, HC |

---

**Item 1(a). Name of Issuer:**
James River Group Holdings, Ltd.

**Item 1(b). Address of Issuer's Principal Executive Offices:**
Clarendon House, 2 Church Street, Hamilton, Pembroke, Bermuda, HM11

**Item 2(a). Name of Person Filing:**
Zimmer Partners, LP, a Delaware limited partnership (the "Investment Manager"), Zimmer Financial Services Group LLC, a Delaware limited liability company ("ZFSG"), Zimmer Partners GP, LLC, a Delaware limited liability company (the "GP"), and Stuart J. Zimmer (collectively, the "Reporting Persons").  ZFSG is the sole member of the GP. Stuart J. Zimmer, a revocable trust for his benefit, and an irrevocable trust for his immediate family are the sole members of ZFSG.  The GP is the general partner of the Investment Manager.  The Investment Manager is the investment manager of Zimmer Master Infrastructure Fund, L.P. and ZP Master MidCap Fund, Ltd., (together, the "Zimmer Accounts").

**Item 2(b). Address of Principal Business Office:**
The address of the principal business office of each of the Reporting Persons is c/o Zimmer Partners, LP, 9 West 57th Street, 33rd Floor
New York, NY 10019.

**Item 2(c). Citizenship:**
Delaware

**Item 2(d). Title of Class of Securities:**
Common Shares, par value $0.0002 per share

**Item 2(e). CUSIP Number:**
G5005R107

**Item 3. If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:**

(a) [ ] Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).

(b) [ ] Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).

(c) [ ] Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).

(d) [ ] Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).

(e) [x] An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);

(f) [ ] An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);

(g) [x] A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);

(h) [ ] A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i) [ ] A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

(j) [ ] A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), if filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:

(k) [ ] Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).

**Item 4. Ownership:**

**(a) Amount beneficially owned:**

The Reporting Persons may be deemed the beneficial owners of 4,591,638 shares of Common Stock. The Reporting Persons may be deemed the beneficial owners of approximately 9.9955% of the outstanding shares of Common Stock.  This percentage was determined by dividing 4,591,638 by 45,936,898, which is the number of shares of Common Stock outstanding as of September 30, 2025, as reported in the Issuer's Form 10-Q filed on November 4, 2025 with the Securities and Exchange Commission. The Reporting Persons have the shared power to vote and dispose of the 4,591,638 shares of Common Stock beneficially owned.

**(b) Percent of class:**

9.9955

**(c) Number of shares as to which the person has:**

**(i) Sole power to vote or to direct the vote:**

0

**(ii) Shared power to vote or to direct the vote:**

4,591,638

**(iii) Sole power to dispose or to direct the disposition of:**

0

**(iv) Shared power to dispose or to direct the disposition of:**

4,591,638

**Item 5. Ownership of Five Percent or Less of a Class.**

[x] If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following.

**Item 6. Ownership of More than 5 Percent on Behalf of Another Person.**

Not Applicable

**Item 7. Identification and Classification of the Subsidiary**

Not Applicable

**Item 8. Identification and Classification of Members of the Group**

Not Applicable

**Item 9. Notice of Dissolution of Group**

Not Applicable

**Item 10. Certification:**

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.

### 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.

**Zimmer Partners, LP**

**Date:** 11/12/2025

**By:** /s/ Jelena Napolitano

**Name & Title:** Jelena Napolitano/ Authorized Person

**Zimmer Financial Services Group LLC**

**Date:** 11/12/2025

**By:** /s/ Stuart J. Zimmer

**Name & Title:** Stuart J. Zimmer / Director

**Zimmer Partners GP, LLC**

**Date:** 11/12/2025

**By:** /s/ Stuart J. Zimmer

**Name & Title:** Stuart J. Zimmer / Director, Zimmer Financial Services Group LLC, its Managing Member

**Stuart J. Zimmer**

**Date:** 11/12/2025

**By:** /s/ Stuart J. Zimmer

**Name & Title:** Stuart J. Zimmer / Self