SEC Form 4 reporting owner

Sakakibara Shan Riku

Sakakibara Shan Riku has filed 9 Form 4 transactions reported between June 8, 2026 and September 10, 2026, as Chief Product Officer of BillionToOne, Inc..

Name as filed: Sakakibara Shan Riku

Open-market buys, 24 mo
None
reported
Open-market sales, 24 mo
$1.4M
3 lines
Companies
1
with Form 4 filings
Latest transaction
Sep 10, 2026
transaction date

Roles and reported holdings

  • BLLNBillionToOne, Inc.
    Jun 8, 2026 – Sep 10, 2026

    Chief Product Officer

    Held directly196,500 sh as of Sep 10, 2026 · Form 4

    24 months: $1.4M sold

Transaction history

All 9 reported transactions, newest first. Every row links to the Form 4 on SEC EDGAR.

DateCompanyTypeSharesValueFiling
Sep 10, 2026BLLNChief Product OfficerGiftCode G · direct3,500—Form 4
Jul 31, 2026BLLNChief Product OfficerOpen-market saleCode S · direct4,000$561K@ $140.21Form 4
Jul 9, 2026BLLNChief Product OfficerOpen-market saleCode S · direct4,000$500K@ $125.00Form 4
Jul 9, 2026BLLNChief Product OfficerOption exerciseCode M · direct1,354$42K@ $30.78Form 4
Jul 9, 2026BLLNChief Product OfficerOption exerciseCode M · direct1,355$42K@ $30.78Form 4
Jul 9, 2026BLLNChief Product OfficerOption exerciseCode M · direct1,117$34K@ $30.78Form 4
Jul 9, 2026BLLNChief Product OfficerOption exerciseCode M · direct174$2K@ $8.65Form 4
Jun 24, 2026BLLNChief Product OfficerOption exerciseCode M · direct4,000$35K@ $8.65Form 4
Jun 8, 2026BLLNChief Product OfficerOpen-market saleCode S · direct4,000$386K@ $96.45Form 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.