Billiontoone Inc.

11/10/2025 | Press release | Distributed by Public on 11/10/2025 20:39

Statement of Changes in Beneficial Ownership (Form 4)

FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number: 3235-0287
Estimated average burden hours per response... 0.5
(Print or Type Responses)
1. Name and Address of Reporting Person *
Bremner Thomas S
2. Issuer Name and Ticker or Trading Symbol
BillionToOne, Inc. [BLLN]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last) (First) (Middle)
1 NORTH WACKER DRIVE, SUITE 2200
3. Date of Earliest Transaction (Month/Day/Year)
11/06/2025
(Street)
CHICAGO, IL 60606-2807
4. If Amendment, Date Original Filed (Month/Day/Year)
6. Individual or Joint/Group Filing (Check Applicable Line)
_X_ Form filed by One Reporting Person
___ 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 (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 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
Common Stock 11/06/2025 A 8,333(1) A $ 0 8,333 D
Common Stock 11/07/2025 C(2)(3) 152,440 A (3) 152,440 I See Footnotes(4)(11)(12)
Common Stock 11/07/2025 C(2)(3) 155,711 A (3) 155,711 I See Footnotes(5)(11)(12)
Common Stock 11/07/2025 C(2)(3) 176,271 A (3) 176,271 I See Footnotes(6)(11)(12)
Common Stock 11/07/2025 C(2)(3) 269,918 A (3) 269,918 I See Footnotes(7)(11)(12)
Common Stock 11/07/2025 C(2)(3) 240,072 A (3) 240,072 I See Footnotes(8)(11)(12)
Common Stock 11/07/2025 C(2)(3) 675,352 A (3) 675,352 I See Footnotes(9)(11)(12)
Common Stock 11/07/2025 C(2)(3) 277,508 A (3) 277,508 I See Footnotes(10)(11)(12)
Common Stock 11/07/2025 J(13) 8,333 D (13) 0 D
Common Stock 11/07/2025 J(13) 152,440 D (13) 0 I See Footnotes(4)(11)(12)
Common Stock 11/07/2025 J(13) 155,711 D (13) 0 I See Footnotes(5)(11)(12)
Common Stock 11/07/2025 J(13) 176,271 D (13) 0 I See Footnotes(6)(11)(12)
Common Stock 11/07/2025 J(13) 269,918 D (13) 0 I See Footnotes(7)(11)(12)
Common Stock 11/07/2025 J(13) 240,072 D (13) 0 I See Footnotes(8)(11)(12)
Common Stock 11/07/2025 J(13) 675,352 D (13) 0 I See Footnotes(9)(11)(12)
Common Stock 11/07/2025 J(13) 277,508 D (13) 0 I See Footnotes(10)(11)(12)
Class A Common Stock 11/07/2025 J(13) 8,333 A (13) 8,333 D
Class A Common Stock 11/07/2025 J(13) 152,440 A (13) 152,440 I See Footnotes(4)(11)(12)
Class A Common Stock 11/07/2025 J(13) 155,711 A (13) 155,711 I See Footnotes(5)(11)(12)
Class A Common Stock 11/07/2025 J(13) 176,271 A (13) 176,271 I See Footnotes(6)(11)(12)
Class A Common Stock 11/07/2025 J(13) 269,918 A (13) 269,918 I See Footnotes(7)(11)(12)
Class A Common Stock 11/07/2025 J(13) 240,072 A (13) 240,072 I See Footnotes(8)(11)(12)
Class A Common Stock 11/07/2025 J(13) 675,352 A (13) 675,352 I See Footnotes(9)(11)(12)
Class A Common Stock 11/07/2025 J(13) 277,508 A (13) 277,508 I See Footnotes(10)(11)(12)
Class A Common Stock 11/07/2025 P 4,016 A $60 156,456 I See Footnotes(4)(11)(12)
Class A Common Stock 11/07/2025 P 4,084 A $60 159,795 I See Footnotes(5)(11)(12)
Class A Common Stock 11/07/2025 P 3,462 A $60 179,733 I See Footnotes(6)(11)(12)
Class A Common Stock 11/07/2025 P 5,446 A $60 275,364 I See Footnotes(7)(11)(12)
Class A Common Stock 11/07/2025 P 6,867 A $60 246,939 I See Footnotes(8)(11)(12)
Class A Common Stock 11/07/2025 P 17,791 A $60 693,143 I See Footnotes(9)(11)(12)
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 1474 (9-02)
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 (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 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
(Month/Day/Year)
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
Series A-1 Convertible Preferred Stock (3) 11/07/2025 C 1,352 (3) (3) Common Stock 1,352 (3) 0 I See Footnotes(4)(11)(12)
Series C Convertible Preferred Stock (3) 11/07/2025 C 114,117 (3) (3) Common Stock 114,117 (3) 0 I See Footnotes(4)(11)(12)
Series C-1 Convertible Preferred Stock (3) 11/07/2025 C 16,747 (3) (3) Common Stock 16,747 (3) 0 I See Footnotes(4)(11)(12)
Series D Convertible Preferred Stock (3) 11/07/2025 C 20,224 (3) (3) Common Stock 20,224 (3) 0 I See Footnotes(4)(11)(12)
Series C Convertible Preferred Stock (3) 11/07/2025 C 121,688 (3) (3) Common Stock 121,688 (3) 0 I See Footnotes(5)(11)(12)
Series C-1 Convertible Preferred Stock (3) 11/07/2025 C 17,858 (3) (3) Common Stock 17,858 (3) 0 I See Footnotes(5)(11)(12)
Series D Convertible Preferred Stock (3) 11/07/2025 C 16,165 (3) (3) Common Stock 16,165 (3) 0 I See Footnotes(5)(11)(12)
Series A-1 Convertible Preferred Stock (3) 11/07/2025 C 1,562 (3) (3) Common Stock 1,562 (3) 0 I See Footnotes(6)(11)(12)
Series C Convertible Preferred Stock (3) 11/07/2025 C 131,888 (3) (3) Common Stock 131,888 (3) 0 I See Footnotes(6)(11)(12)
Series C-1 Convertible Preferred Stock (3) 11/07/2025 C 19,355 (3) (3) Common Stock 19,355 (3) 0 I See Footnotes(6)(11)(12)
Series D Convertible Preferred Stock (3) 11/07/2025 C 23,466 (3) (3) Common Stock 23,466 (3) 0 I See Footnotes(6)(11)(12)
Series A-1 Convertible Preferred Stock (3) 11/07/2025 C 1,864 (3) (3) Common Stock 1,864 (3) 0 I See Footnotes(7)(11)(12)
Series C Convertible Preferred Stock (3) 11/07/2025 C 157,404 (3) (3) Common Stock 157,404 (3) 0 I See Footnotes(7)(11)(12)
Series C-1 Convertible Preferred Stock (3) 11/07/2025 C 23,100 (3) (3) Common Stock 23,100 (3) 0 I See Footnotes(7)(11)(12)
Series D Convertible Preferred Stock (3) 11/07/2025 C 87,550 (3) (3) Common Stock 87,550 (3) 0 I See Footnotes(7)(11)(12)
Series A-1 Convertible Preferred Stock (3) 11/07/2025 C 652 (3) (3) Common Stock 652 (3) 0 I See Footnotes(8)(11)(12)
Series C Convertible Preferred Stock (3) 11/07/2025 C 55,091 (3) (3) Common Stock 55,091 (3) 0 I See Footnotes(8)(11)(12)
Series C-1 Convertible Preferred Stock (3) 11/07/2025 C 8,084 (3) (3) Common Stock 8,084 (3) 0 I See Footnotes(8)(11)(12)
Series D Convertible Preferred Stock (3) 11/07/2025 C 176,245 (3) (3) Common Stock 176,245 (3) 0 I See Footnotes(8)(11)(12)
Series A-1 Convertible Preferred Stock (3) 11/07/2025 C 5,988 (3) (3) Common Stock 5,988 (3) 0 I See Footnotes(9)(11)(12)
Series C Convertible Preferred Stock (3) 11/07/2025 C 505,570 (3) (3) Common Stock 505,570 (3) 0 I See Footnotes(9)(11)(12)
Series C-1 Convertible Preferred Stock (3) 11/07/2025 C 74,195 (3) (3) Common Stock 74,195 (3) 0 I See Footnotes(9)(11)(12)
Series D Convertible Preferred Stock (3) 11/07/2025 C 89,599 (3) (3) Common Stock 89,599 (3) 0 I See Footnotes(9)(11)(12)
Series A-1 Convertible Preferred Stock (3) 11/07/2025 C 1,078 (3) (3) Common Stock 1,078 (3) 0 I See Footnotes(10)(11)(12)
Series C Convertible Preferred Stock (3) 11/07/2025 C 91,003 (3) (3) Common Stock 91,003 (3) 0 I See Footnotes(10)(11)(12)
Series C-1 Convertible Preferred Stock (3) 11/07/2025 C 13,355 (3) (3) Common Stock 13,355 (3) 0 I See Footnotes(10)(11)(12)
Series D Convertible Preferred Stock (3) 11/07/2025 C 122,072 (3) (3) Common Stock 122,072 (3) 0 I See Footnotes(10)(11)(12)

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Bremner Thomas S
1 NORTH WACKER DRIVE, SUITE 2200
CHICAGO, IL 60606-2807
X

Signatures

/s/ Thomas P. Lynch, Attorney-in-Fact 11/10/2025
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Each restricted stock unit ("RSU") represents a contingent right to receive one share of the Issuer's Common Stock. The RSUs shall vest over three years in equal annual installments on the anniversary of November 6, 2025, subject to the Reporting Person's continuous service to the Issuer through each such vesting date.
(2) The total represents shares received upon conversion of shares of Series A-1 Convertible Preferred Stock, Series C Convertible Preferred Stock, Series C-1 Convertible Preferred Stock and/or Series D Convertible Preferred Stock.
(3) The reported security converted into the Issuer's Common Stock on a one-for-one basis automatically immediately prior to the closing of the Issuer's initial public offering of Class A common stock (the "Offering") without payment of further consideration. The shares have no expiration date.
(4) The reported security is directly held by Adams Street 2019 Direct Growth Equity Fund LP.
(5) The reported security is directly held by Adams Street 2020 Direct Growth Equity Fund LP.
(6) The reported security is directly held by Adams Street 2021 Direct Growth Equity Fund LP.
(7) The reported security is directly held by Adams Street 2022 Direct Growth Equity Fund LP.
(8) The reported security is directly held by Adams Street Private Equity Navigator Fund LLC (f/k/a Adams Street Global Private Markets Fund LP).
(9) The reported security is directly held by Adams Street Growth Equity Fund VII LP.
(10) The reported security is directly held by FCPR GF - Lumyna Private Equity World Fund.
(11) Adams Street Partners, LLC is the managing member of the general partner of each of Adams Street 2019 Direct Growth Equity Fund LP, Adams Street 2020 Direct Growth Equity Fund LP, Adams Street 2021 Direct Growth Equity Fund LP, Adams Street 2022 Direct Growth Equity Fund LP, Adams Street Growth Equity Fund VII LP, and Adams Street Private Equity Navigator Fund LLC (f/k/a Adams Street Global Private Markets Fund LP) (collectively, the U.S. Funds) and, as a result, may be deemed to beneficially own the shares held by the U.S. Funds. Furthermore, Adams Street Partners, LLC, is the Sous-Delegataire Financier of the Delegataire Financier of the management company of FCPR GF - Lumyna Private Equity World Fund (Lumyna and together with the U.S. Funds, the Funds) and, as a result, may be deemed to beneficially own the shares held by Lumyna.
(12) (Continued from footnote 11) Thomas S. Bremner, Jeffrey T. Diehl, Brian Dudley, Elisha P. Gould, Robin Murray and Fred Wang, each of whom is a partner of Adams Street Partners, LLC (or a subsidiary thereof), may be deemed to have shared voting, investment and dispositive power over the shares held by the Funds. The Reporting Person disclaims beneficial ownership of these shares except to the extent of his pecuniary interest therein.
(13) Pursuant to a reclassification exempt under Rule 16b-7, each share of Common Stock was automatically reclassified into one share of Class A common stock immediately prior to the completion of the Offering.
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure. Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.
Billiontoone Inc. published this content on November 10, 2025, and is solely responsible for the information contained herein. Distributed via Edgar on November 11, 2025 at 02:39 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]