Sec Form 3 Filing - BSIV Hold 101, LP @ Neptune Insurance Holdings Inc. - 2025-09-30

FORM 3 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person BSIV Hold 101, LP 2. Issuer Name and Ticker or Trading Symbol Neptune Insurance Holdings Inc. [ NP] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director X __ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) 200 PARK AVENUE, 45TH FLOOR, 3. Date of Earliest Transaction (MM/DD/YY) 09/30/2025 (Street) NEW YORK, NY10166 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) _____ Form filed by One Reporting Person __ X __ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Class A Common Stock 20,350,595 D ( 1 ) ( 2 )

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other BSIV Hold 101, LP 200 PARK AVENUE, 45TH FLOOR NEW YORK, NY10166 X BSIV Hold 101 GP, LLC 200 PARK AVENUE, 45TH FLOOR NEW YORK, NY10166 X Bregal Sagemount IV General Partner Jersey Ltd SECOND FLOOR, WINDWARD HOUSE, LA ROUTE DE LA LIBERATION ST. HELIER, JERSEY, Y9JE2 3BQ X Bregal Sagemount Management LP 200 PARK AVENUE, 45TH FLOOR NEW YORK, NY10166 X Yoon Gene 200 PARK AVENUE, 45TH FLOOR NEW YORK, NY10166 X Signatures BSIV Hold 101, LP, By: BSIV Hold 101 GP, LLC, its GP, By: Bregal Sagemount IV General Partner Jersey Limited, its Sole Member, By: /s/ Colin James Dow, Name: Colin James Dow, Director; /s/ Paul Andrew Bradshaw, Name: Paul Andrew Bradshaw, Director 09/30/2025 Signature of Reporting Person Date BSIV Hold 101 GP, LLC, By: Bregal Sagemount IV General Partner Jersey Limited, its Sole Member, By: /s/ Colin James Dow, Name: Colin James Dow, Title: Director, /s/ Paul Andrew Bradshaw, Name: Paul Andrew Bradshaw, Title: Director 09/30/2025 Signature of Reporting Person Date Bregal Sagemount IV General Partner Jersey Limited, By: /s/ Colin James Dow, Name: Colin James Dow, Title: Director, /s/ Paul Andrew Bradshaw, Name: Paul Andrew Bradshaw, Title: Director 09/30/2025 Signature of Reporting Person Date Bregal Sagemount Management LP, By: /s/ Eugene Yoon, Name: Eugene Yoon, Title: Managing Partner 09/30/2025 Signature of Reporting Person Date Michelle Riley, as attorney-in-fact for Gene Yoon 09/30/2025 Signature of Reporting Person Date

Explanation of Responses:

( 1 )The reported securities are held directly by BSIV Hold 101, LP ("BSIV 101"). BSIV 101 is managed by BSIV Hold 101 GP, LLC, its general partner, which is managed by Bregal Sagemount IV General Partner Jersey Limited, its sole member, which is managed by a board of directors and is ultimately 100% owned by Gene Yoon. Bregal Sagemount Management LP, which is majority owned by Gene Yoon, is the investment advisor to BSIV 101. ( 2 )Each of the reporting persons disclaims beneficial ownership of the reported securities, except to the extent of such reporting person's pecuniary interest therein, if any. The filing of this statement shall not be deemed an admission by any reporting person of beneficial ownership of the reported securities.

Remarks: Exhibit 24.1 - Power of Attorney

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

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