Nancy JoAnn Johnson - 08 Jun 2026 Form 4 Insider Report for BillionToOne, Inc. (BLLN)

Reporting relationship: Senior Vice President of Sales and Commercial Operations
Issuer ticker: BLLN
Reported as of: 08 Jun 2026
Net transaction value: -$1,402,540
SEC form: 4
Accepted by SEC: 10 Jun 2026, 20:36:25 UTC
Prior SEC filing: 12 Nov 2025
Source filing: View source filing
Reporting owner signature: /s/ Thomas P. Lynch, Attorney-in-Fact

Key filing fact

Nancy JoAnn Johnson filed Form 4 for BillionToOne, Inc. (BLLN) on 10 Jun 2026.

Key facts

This page summarizes Nancy JoAnn Johnson's Form 4 filing for BillionToOne, Inc. (BLLN).
7 reported transactions and 0 derivative rows are listed below.
Accepted by SEC: 10 Jun 2026, 20:36.

Change

Previous filing in this sequence was filed on 12 Nov 2025.
Current net transaction value: -$1,402,540.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0002087387 Primary reporting owner

Johnson Nancy JoAnn

Relationship: Senior Vice President of Sales and Commercial Operations
Address: C/O BILLIONTOONE, INC., 1035 O'BRIEN DRIVE, MENLO PARK
Signature: /s/ Thomas P. Lynch, Attorney-in-Fact
Signature date: 10 Jun 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

BLLN transaction

Class A Common Stock

Sale

Transaction value: $289,135
Shares: -2,918
Change %: -8.1%
Price: $99.09
Shares after: 32,982
Date: 08 Jun 2026
Ownership: Direct
Footnotes: F1, F2

BLLN transaction

Class A Common Stock

Sale

Transaction value: $30,015
Shares: -300
Change %: -0.91%
Price: $100.05
Shares after: 32,682
Date: 08 Jun 2026
Ownership: Direct
Footnotes: F1, F3

BLLN transaction

Class A Common Stock

Sale

Transaction value: $20,197
Shares: -200
Change %: -0.61%
Price: $100.98
Shares after: 32,482
Date: 08 Jun 2026
Ownership: Direct
Footnotes: F1, F4

BLLN transaction

Class A Common Stock

Sale

Transaction value: $463,204
Shares: -4,666
Change %: -14%
Price: $99.27
Shares after: 27,816
Date: 09 Jun 2026
Ownership: Direct
Footnotes: F1, F5

BLLN transaction

Class A Common Stock

Sale

Transaction value: $273,714
Shares: -2,700
Change %: -9.7%
Price: $101.38
Shares after: 25,116
Date: 09 Jun 2026
Ownership: Direct
Footnotes: F1, F6

BLLN transaction

Class A Common Stock

Sale

Transaction value: $185,843
Shares: -1,816
Change %: -7.2%
Price: $102.34
Shares after: 23,300
Date: 09 Jun 2026
Ownership: Direct
Footnotes: F1, F7

BLLN transaction

Class A Common Stock

Sale

Transaction value: $140,431
Shares: -1,400
Change %: -6%
Price: $100.31
Shares after: 21,900
Date: 09 Jun 2026
Ownership: Direct
Footnotes: F1, F8

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Rule 10b5-1 trading plan

These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.

Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).

Explanation of responses 8 footnotes

Footnote F1

The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.

Footnote F2

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $98.900 to $99.690 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F3

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $99.960 to $100.220 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F4

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $100.980 to $100.990 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F5

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $98.900 to $99.870 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F6

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $100.990 to $101.710 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F7

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $101.990 to $102.570 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Footnote F8

The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $99.990 to $100.720 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

SEC remarks

Senior Vice President of Sales and Commercial Operations