Form4insider filings, from the source

Company · CIK 0002070849 · SIC 8071 — Services-Medical Laboratories · Nasdaq

BillionToOne, Inc. · BLLN

Insider activity reported against this company. All insider holders · On EDGAR ↗

1M3M6M1Y2YAll datashares as filed — not split-adjusted
Open-market buys & salesbuys $0 · 0sales $11.2M · 6net −$11.2M
$10k$10k$100k$100k$1M$1M$10M$10MbuyssalesAug 28Sep 2Sep 7Sep 12Sep 17Sep 23Sep 28

Reported at this company — common stock

TradeReported (ET)InsiderSharesAvg priceTotalOwned afterΔ stakeFlags
Sep 21, 2026 SForm 4 →Sep 23, 5:50 pm EDTJohn Roderick ten BoschSVP of Laboratory Operations1,416$106.61$150,96023,635−5.65%10b5-1
Sep 17, 2026 SForm 4 →Sep 21, 7:00 pm EDTThomas P. LynchSee Remarks35,112$110.33$3,873,966700−98.0%10b5-1
Sep 17, 2026 MForm 4 →Sep 21, 7:00 pm EDTThomas P. LynchSee Remarks35,112$13.61$477,89835,812—10b5-1
Sep 14, 2026 SForm 4 →Sep 16, 6:43 pm EDTOguzhan AtayChairman and CEO, Director30,331$99.91$3,030,444157,168−16.2%10b5-1
Sep 14, 2026 MForm 4 →Sep 16, 6:43 pm EDTOguzhan AtayChairman and CEO, Director24,999$2.80$69,99724,999—10b5-1
Sep 10, 2026 GForm 4 →Sep 14, 6:47 pm EDTShan Riku SakakibaraChief Product Officer3,500——196,500—
Sep 9, 2026 SForm 4 →Sep 11, 6:01 pm EDTJohn Roderick ten BoschSVP of Laboratory Operations1,416$97.54$138,11725,051−5.35%10b5-1
Sep 9, 2026 SForm 4 →Sep 11, 6:01 pm EDTDavid TsaoChief Technology Officer, Director20,000$98.77$1,975,4001,000−95.2%10b5-1
Sep 9, 2026 MForm 4 →Sep 11, 6:01 pm EDTDavid TsaoChief Technology Officer, Director20,000$2.80$56,00021,000—10b5-1
Sep 8, 2026 SForm 4 →Sep 10, 7:44 pm EDTThomas P. LynchSee Remarks20,000$99.99$1,999,880700−96.6%10b5-1
Sep 8, 2026 MForm 4 →Sep 10, 7:44 pm EDTThomas P. LynchSee Remarks20,000$13.61$272,20020,700—10b5-1
Sep 8, 2026 CGForm 4 →Sep 10, 7:44 pm EDTOguzhan AtayChairman and CEO, Director40,000——0—
Sep 3, 2026 CGForm 4 →Sep 8, 9:55 pm EDTDavid TsaoChief Technology Officer, Director40,000——1,000—

Reported at this company — derivatives (options, RSUs, warrants)

TradeReported (ET)InsiderSharesAvg priceTotalOwned afterΔ stakeFlags
Sep 17, 2026 MForm 4 →Sep 21, 7:00 pm EDTThomas P. LynchSee Remarks35,112$13.61$477,89830,834—10b5-1
Sep 14, 2026 MForm 4 →Sep 16, 6:43 pm EDTOguzhan AtayChairman and CEO, Director24,999$2.80$69,997501,962—10b5-1
Sep 9, 2026 MForm 4 →Sep 11, 6:01 pm EDTDavid TsaoChief Technology Officer, Director20,000$2.80$56,000560,000—10b5-1
Sep 8, 2026 MForm 4 →Sep 10, 7:44 pm EDTThomas P. LynchSee Remarks20,000$13.61$272,20036,674—10b5-1
Sep 8, 2026 CForm 4 →Sep 10, 7:44 pm EDTOguzhan AtayChairman and CEO, Director20,000——2,197,542—
Sep 3, 2026 CForm 4 →Sep 8, 9:55 pm EDTDavid TsaoChief Technology Officer, Director20,000——2,305,108—