Company · Ownership research

BillionToOne, Inc. BLLN

CIK 0002070849

Form 4 transactions dated Oct 1, 2023 to Oct 15, 2026, as reported to the SEC.

Insider trading Initial holdings Institutional holders

This page lists 30 of 172 rows; the complete set is available through the API.

Insider filings on file run through Sep 30, 2026.

Some filings are submitted jointly by several insiders. The SEC form does not apportion the reported figures between them, so results include every joint filer.

Insider purchases & sales

Purchased: $3.18M
Sold: $45.97M

Oct 1, 2023 – Sep 30, 2026
Available records · partial months are marked ·

20256 of 6 preview events

Date	Insider	Activity	Trade value (USD)	% of prior holding
Nov 7, 2025	Lynch Thomas P. See Remarks	Purchase	$6.00K 100 shares bought	16.67% added Direct holding	▾
Nov 7, 2025	Tsao David Chief Technology Officer · Director	Purchase	$60.00K 1,000 shares bought	New holding Direct holding	▾
Nov 7, 2025	ten Bosch John Roderick See Remarks	Purchase	$48.00K 800 shares bought	2.16% added Direct holding	▾
Nov 7, 2025	Johnson Nancy JoAnn See Remarks	Purchase	$414.00K 6,900 shares bought	23.79% added Direct holding	▾
Nov 7, 2025	Rai Akshay Director	Purchase	$150.00K 2,500 shares bought	22.71% added Direct holding	▾
Nov 7, 2025	Bremner Thomas S Director	Purchase	$2.50M 41,666 shares bought	Unavailable Indirect holding	▾

Showing 6 / 6 record groups in 2025. The complete set is available through the API.

BillionToOne, Inc. · BLLN

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The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. For the year shown, this page lists 6 of 6 purchase / sale groups and 30 of 172 other groups; the totals and the monthly series cover the whole window.

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{"ticker":"BLLN","transaction_code":["P","S"],"transaction_form_type":"4","page_size":20}

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Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.

Non-cancelled, non-derivative purchase (P) and sale (S) rows dated inside the public window, as reported. Share totals are on today's split-adjusted basis. Includes open-market and private transactions. Data after the latest filing is not asserted complete and is not zero-filled. A grouped event shares filing, transaction date, security, code, direction, ownership bucket and source. Derivative groups also match underlying security, exercise price, exercise/expiration dates and footnote references. Reported rows are retained; P/S price lots can be grouped. Post-transaction balances are never summed.