Item 5. Other Information
Item 5. Other Information
Disclosure of Trading Arrangements
During the fiscal quarter ended June 30, 2026, none of our directors or officers (as defined in Rule 16a-1(f) under the Exchange Act) adopted or terminated a “Rule 10b5-1 trading arrangement” or a “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408 of Regulation S-K, except as described in the paragraphs below.
On June 2, 2026 , John ten Bosch , our Senior Vice President of Laboratory Operations , entered into a pre-arranged stock trading plan. Such trading plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. Mr. ten Bosch’s plan provides for, subject to certain market price limits and other terms set forth in the plan, the sale of up to 12,750 shares of Class A common stock between September 9, 2026 and December 4, 2026 .
On June 5, 2026 , Oguzhan Atay , our Chief Executive Officer and the Chair of our Board of Directors , entered into a pre-arranged stock trading plan. Such trading plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. Mr. Atay’s plan provides for, subject to certain market price limits and other terms set forth in the plan, the exercise of up to 100,000 stock options and sale of the underlying shares of Class A common stock, between September 14, 2026 and November 27, 2026 .
On June 5, 2026 , David Tsao , our President, Chief Technology Officer and a member of our Board of Directors , entered into a pre-arranged stock trading plan. Such trading plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. Mr. Tsao’s plan provides for, subject to certain market price limits and other terms set forth in the plan, the exercise of up to 70,000 stock options and sale of the underlying shares of Class A common stock, between September 9, 2026 and December 4, 2026 .
On June 8, 2026 , Thomas Lynch , our General Counsel , entered into a pre-arranged stock trading plan. Such trading plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. Mr. Lynch’s plan provides for, subject to certain market price limits and other terms set forth in the plan, the exercise of up to 38,226 stock options and sale of the underlying shares of Class A common stock, between September 8, 2026 and December 9, 2026 .
On June 8, 2026 , Shan Riku Sakakibara , our Chief Product Officer , entered into a pre-arranged stock trading plan. Such trading plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. Ms. Sakakibara’s plan provides for, subject to certain market price limits and other terms set forth in the plan, (a) the sale of up to 12,000 shares of Class A common stock, and (b) the exercise of up to 8,000 stock options and sale of the underlying shares of Class A common stock, between September 8, 2026 and December 9, 2026 .
On June 9, 2026 , Nancy Johnson , our Senior Vice President of Sales and Commercial Operations , entered into a pre-arranged stock trading plan. Such trading plan is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. Ms. Johnson’s plan provides for, subject to certain market price limits and other terms set forth in the plan, (a) the sale of up to 25,582 shares of Class A common stock, and (b) the exercise of up to 30,000 stock options and sale of the underlying shares of Class A common stock, between October 1, 2026 and December 31, 2026 , to the extent such trades were not previously executed under Ms. Johnson’s prior stock trading plan entered into on March 6, 2026, which terminates on August 31, 2026
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Item 6. Exhibits
(a) Exhibits
Exhibit No Description of Exhibit Form File No. Exhibit Number Filing Date Filed or Furnished Herewith
3.1 Amended and Restated Certificate of Incorporation of the Registrant
8-K 001-42934 3.1 November 10, 2025
3.2 Amended and Restated Bylaws of Registrant
8-K 001-42934 3.2 November 10, 2025
10.1 Lease Agreement between BillionToOne, Inc. and TPI Investors 21, LLC, dated April 19, 2024
X
10.2 First Amendment to Lease Agreement between BillionToOne, Inc. and Tarlton-Reger Owner, LLC (as successor-in-interest to TPI Investors 21, LLC), dated August 29, 2025
X
10.3 Lease Agreement between BillionToOne, Inc. and Whipple Road Portfolio, LLC, dated June 23 2026
X
31.1 Certification of Chief Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
X
31.2 Certification of Chief Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002
X
32.1* Certification of Chief Executive Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
X
32.2* Certification of Chief Financial Officer pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
X
101.INS Inline XBRL Instance Document (the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document)
101.SCH Inline XBRL Taxonomy Extension Schema Document
101.CAL Inline XBRL Taxonomy Extension Calculation Linkbase Document
101.DEF Inline XBRL Taxonomy Extension Definition Linkbase Document
101.LAB Inline XBRL Taxonomy Extension Label Linkbase Document
101.PRE Inline XBRL Taxonomy Extension Presentation Linkbase Document
104 Cover Page formatted as Inline XBRL and contained in Exhibit 101
_________________________
* The certifications furnished in Exhibits 32.1 and 32.2 are not deemed “filed” for purposes of Section 18 of the Exchange Act, or otherwise subject to the liability of that section, nor shall they be deemed incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended.
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Signatures
Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized.
BillionToOne, Inc.
Date: August 5, 2026 By:
/s/ Oguzhan Atay
Oguzhan Atay
Chief Executive Officer
(Principal Executive Officer)
Date: August 5, 2026 By:
/s/ Ross Taylor
Ross Taylor
Chief Financial Officer
(Principal Financial and Accounting Officer)
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