SEC Form 4 reporting owner

Tsao David

Tsao David has filed 28 Form 4 transactions reported between June 15, 2026 and September 9, 2026, as Chief Technology Officer of BillionToOne, Inc..

Name as filed: Tsao David

Open-market buys, 24 mo

None

reported

Open-market sales, 24 mo

$4.5M

21 lines

Companies

with Form 4 filings

Latest transaction

Sep 9, 2026

transaction date

Roles and reported holdings

BLLNBillionToOne, Inc.
Jun 15, 2026 – Sep 9, 2026
Chief Technology Officer
Held directly1,000 sh as of Sep 8, 2026 · Form 4
24 months: $4.5M sold

Transaction history

All 28 reported transactions, newest first. Every row links to the Form 4 on SEC EDGAR.

Date	Company	Type	Shares	Price	Value	Owned after	Filing
Sep 9, 2026	BLLNChief Technology Officer	Option exerciseCode M · direct	10,000	$2.80	$28K@ $2.80	11,000	Form 4
Sep 8, 2026	BLLNChief Technology Officer	GiftCode G · direct	20,000	—	—	1,000	Form 4
Sep 3, 2026	BLLNChief Technology Officer	Conversion of derivativeCode C · direct	20,000	—	—	21,000	Form 4
Aug 25, 2026	BLLNChief Technology Officer	Option exerciseCode M · direct	10,000	$2.80	$28K@ $2.80	11,000	Form 4
Aug 10, 2026	BLLNChief Technology Officer	Option exerciseCode M · direct	10,000	$2.80	$28K@ $2.80	11,000	Form 4
Jul 13, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	1,028	$126.90	$130K@ $126.90	1,000	Form 4
Jul 13, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	3,835	$125.76	$482K@ $125.76	2,028	Form 4
Jul 13, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	1,725	$124.65	$215K@ $124.65	5,863	Form 4
Jul 13, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	2,274	$123.71	$281K@ $123.71	7,588	Form 4
Jul 13, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	1,138	$122.84	$140K@ $122.84	9,862	Form 4
Jul 13, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	821	$126.89	$104K@ $126.89	11,000	Form 4
Jul 13, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	3,185	$125.85	$401K@ $125.85	11,821	Form 4
Jul 13, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	2,415	$124.90	$302K@ $124.90	15,006	Form 4
Jul 13, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	2,477	$123.84	$307K@ $123.84	17,421	Form 4
Jul 13, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	1,102	$122.90	$135K@ $122.90	19,898	Form 4
Jul 13, 2026	BLLNChief Technology Officer	Option exerciseCode M · direct	10,000	$2.80	$28K@ $2.80	11,000	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	563	$104.32	$59K@ $104.32	1,000	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	2,398	$103.63	$249K@ $103.63	1,563	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	2,978	$102.60	$306K@ $102.60	3,961	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	2,461	$101.37	$249K@ $101.37	6,939	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	1,000	$100.05	$100K@ $100.05	9,400	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	600	$98.74	$59K@ $98.74	10,400	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	230	$104.47	$24K@ $104.47	11,000	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	2,889	$103.68	$300K@ $103.68	11,230	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	2,816	$102.77	$289K@ $102.77	14,119	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	2,361	$101.55	$240K@ $101.55	16,935	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Open-market saleCode S · direct	1,704	$100.37	$171K@ $100.37	19,296	Form 4
Jun 15, 2026	BLLNChief Technology Officer	Option exerciseCode M · direct	10,000	$2.80	$28K@ $2.80	11,000	Form 4

How this page is built

Every row comes from a Form 4 filed with the SEC, which officers, directors and holders of more than 10% of a company’s stock must file within two business days of a trade. Transactions are grouped by the reporting owner’s name as filed (spacing, capitals and punctuation ignored); two different people filing under an identical name would appear together, and one person filing under two spellings appears on two pages.

Open-market totals count code P purchases and code S sales over the last 24 months. The same trade reported on more than one filing is counted once; when another owner (for example a fund and its general partner) reports the identical trade, they are listed beside it. Holdings are the shares owned after the latest purchase, sale, gift or tax-withholding line, shown separately for direct and indirect ownership; an indirect figure is one holding line, not a total across every trust or entity.

This page describes what was filed with the SEC; it is not investment advice or a recommendation to buy or sell any security.