# EDGAR Filing Document

**Accession Number:** 0002047497
**File Stem:** 0001104659-25-107113
**Filing Date:** 2025-11
**Character Count:** 13649
**Document Hash:** 7abc07c1477a226c107ba873fd68bdff
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-25-107113.hdr.sgml**: 20251105

**ACCESSION NUMBER**: 0001104659-25-107113

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13G

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20251105

**DATE AS OF CHANGE**: 20251105

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Rithm Acquisition Corp.
- **CENTRAL INDEX KEY:** 0002047497
- **STANDARD INDUSTRIAL CLASSIFICATION:** BLANK CHECKS [6770]
- **ORGANIZATION NAME:** 05 Real Estate & Construction
- **EIN:** 000000000
- **STATE OF INCORPORATION:** E9
- **FISCAL YEAR END:** 0930

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13G
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-95007
- **FILM NUMBER:** 251455174

**BUSINESS ADDRESS:**
- **STREET 1:** 799 BROADWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10003
- **BUSINESS PHONE:** (212) 850-7770

**MAIL ADDRESS:**
- **STREET 1:** 799 BROADWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10003
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Rithm Acquisition Corp Sponsor LLC
- **CENTRAL INDEX KEY:** 0002047503

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1230

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

**BUSINESS ADDRESS:**
- **STREET 1:** 799 BROADWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10003
- **BUSINESS PHONE:** (212) 850-7770

**MAIL ADDRESS:**
- **STREET 1:** 799 BROADWAY
- **STREET 2:** 8TH FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10003

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

## SCHEDULE 13G

### Under the Securities Exchange Act of 1934

**Issuer:** Rithm Acquisition Corp.

**Title of Class of Securities:** Class A Ordinary Shares, par value $0.0001 per share

**CUSIP Number:** G75751100

**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:**

- [ ] Rule 13d-1(b)

- [ ] Rule 13d-1(c)

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

---

| 1. | Names of Reporting Persons<br>Rithm Acquisition Corp Sponsor LLC | Names of Reporting Persons<br>Rithm Acquisition Corp Sponsor 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>6335000.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 6. | Shared Voting Power<br>0.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 7. | Sole Dispositive Power<br>6335000.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 8. | Shared Dispositive Power<br>0.00 |
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person<br>6335000.00 | Aggregate Amount Beneficially Owned by Each Reporting Person<br>6335000.00 |
| 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>21.5% | Percent of Class Represented by Amount in Row (9)<br>21.5% |
| 12. | Type of Reporting Person (See Instructions)<br>PN | Type of Reporting Person (See Instructions)<br>PN |

**Comment for Type of Reporting Person:** Row 5, 7, 9, and 11: See Item 4 below. Rithm Acquisition Corp Sponsor LLC holds 5,675,000 Class B ordinary shares of the Issuer, which are automatically convertible into the Issuer's Class A ordinary shares, and 660,000 Class A ordinary shares included in the private placement units, in each case as more fully described under the heading "Description of Securities" in the Issuer's registration statement on Form S-1 (File No. 333-284671).

---

| 1. | Names of Reporting Persons<br>Rithm Capital Corp. | Names of Reporting Persons<br>Rithm Capital Corp. |
|:---|:---|:---|:---|
| 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>0.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 6. | Shared Voting Power<br>6335000.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 7. | Sole Dispositive Power<br>0.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 8. | Shared Dispositive Power<br>6335000.00 |
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person<br>6335000.00 | Aggregate Amount Beneficially Owned by Each Reporting Person<br>6335000.00 |
| 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>21.5% | Percent of Class Represented by Amount in Row (9)<br>21.5% |
| 12. | Type of Reporting Person (See Instructions)<br>PN | Type of Reporting Person (See Instructions)<br>PN |

**Comment for Type of Reporting Person:** Row 6, 8, 9, and 11: See Item 4 below. Rithm Acquisition Corp Sponsor LLC holds 5,675,000 Class B ordinary shares of the Issuer, which are automatically convertible into the Issuer's Class A ordinary shares, and 660,000 Class A ordinary shares included in the private placement units, in each case as more fully described under the heading "Description of Securities" in the Issuer's registration statement on Form S-1 (File No. 333-284671).

---

| 1. | Names of Reporting Persons<br>Michael Nierenberg | Names of Reporting Persons<br>Michael Nierenberg |
|:---|:---|:---|:---|
| 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>0.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 6. | Shared Voting Power<br>6335000.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 7. | Sole Dispositive Power<br>0.00 |
| Number of<br>Shares<br>Beneficially<br>Owned by<br>Each<br>Reporting<br>Person<br>With | 8. | Shared Dispositive Power<br>6335000.00 |
| 9. | Aggregate Amount Beneficially Owned by Each Reporting Person<br>6335000.00 | Aggregate Amount Beneficially Owned by Each Reporting Person<br>6335000.00 |
| 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>21.5% | Percent of Class Represented by Amount in Row (9)<br>21.5% |
| 12. | Type of Reporting Person (See Instructions)<br>PN | Type of Reporting Person (See Instructions)<br>PN |

**Comment for Type of Reporting Person:** Row 6, 8, 9, and 11:  See Item 4 below. Rithm Acquisition Corp Sponsor LLC holds 5,675,000 Class B ordinary shares of the Issuer, which are automatically convertible into the Issuer's Class A ordinary shares, and 660,000 Class A ordinary shares included in the private placement units, in each case as more fully described under the heading "Description of Securities" in the Issuer's registration statement on Form S-1 (File No. 333-284671).

---

**Item 1(a). Name of Issuer:**
Rithm Acquisition Corp.

**Item 1(b). Address of Issuer's Principal Executive Offices:**
799 Broadway, 8th Floor, New York, NY 10003

**Item 2(a). Name of Person Filing:**
Rithm Acquisition Sponsor LLC

Rithm Capital Corp.

**Item 2(b). Address of Principal Business Office:**
c/o Rithm Acquisition Corp.
799 Broadway, 8th Floor
New York, New York 10003

**Item 2(c). Citizenship:**
The citizenship of Rithm Acquisition Sponsor LLC is Delaware.

The citizenship of Rithm Capital Corp. is Delaware.

The citizenship of Michael Nierenberg is the United States.

**Item 2(d). Title of Class of Securities:**
Class A Ordinary Shares, par value $0.0001 per share

**Item 2(e). CUSIP Number:**
G75751100

**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) [ ] 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) [ ] 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 responses to Items 5-11 of the cover pages of this Schedule 13G are incorporated herein by reference.
As of September 30, 2025, the Reporting Persons may be deemed to beneficially own 6,335,000 shares of the Issuer's Class A and Class B ordinary shares, representing 21.5% of the total shares of Class A and Class B ordinary shares issued and outstanding. The Class B ordinary shares are automatically convertible into the Issuer's Class A ordinary shares at the time of the Issuer's initial business combination on a one-for-one basis, subject to adjustment, as more fully described under the heading "Description of Securities - Founder Shares" in the Issuer's registration statement on Form S-1 (File No. 333-284671).
Rithm Acquisition Sponsor LLC is the record holder of such ordinary shares, and Rithm Acquisition Sponsor LLC is controlled by Rithm Capital Corp., an affiliate of the Issuer, and Michael Nierenberg as a result of his role as chief executive officer, chairman of the board and president of Rithm Capital Corp. As a result, each of Rithm Acquisition Sponsor LLC, Rithm Capital Corp. and Mr. Nierenberg may be deemed to have beneficial ownership of the Class A and Class B ordinary shares held by Rithm Acquisition Sponsor LLC, but each disclaims such beneficial ownership except to the extent of such person's or entity's pecuniary interest therein.

**(b) Percent of class:**

See responses to Item 11 on each cover page.

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

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

See responses to Item 5 on each cover page.

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

See responses to Item 6 on each cover page.

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

See responses to Item 7 on each cover page.

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

See responses to Item 8 on each cover page.

**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:**

—

### 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.

**Rithm Acquisition Corp Sponsor LLC**

**Date:** 11/05/2025

**By:** /s/ Nicola Santoro

**Name & Title:** Nicola Santoro, Chief Financial Officer of Rithm Acquisition Sponsor LLC

**Rithm Capital Corp.**

**Date:** 11/05/2025

**By:** /s/ Nicola Santoro

**Name & Title:** Nicola Santoro, Chief Financial Officer of Rithm Capital Corp.

**Michael Nierenberg**

**Date:** 11/05/2025

**By:** /s/ Michael Nierenberg

**Name & Title:** Michael Nierenberg