SEC Form 4 · accession 0002070849-26-000052
BillionToOne, Inc. · BLLN
Statement of changes in beneficial ownership, as filed. Original on EDGAR ↗
Reporting owner
Oguzhan Atay
Officer — Chairman and CEO · Director
Period of report
Aug 3, 2026
Accepted (ET)
Aug 5, 2026 · 8:52 pm EDT
Rule 10b5-1 plan
yes — trade under a plan
Issuer CIK
0002070849
Table I — non-derivative securities
| Security | Date | Code | Shares | Price | A/D | Owned after | D/I | Nature of ownership |
|---|---|---|---|---|---|---|---|---|
| Class A Common Stock | Aug 3, 2026 | M | 20,000 | $2.80 | A | 20,000 | D | |
| Class A Common Stock | Aug 3, 2026 | M | 6,250 | $2.80 | A | 26,250 | D | |
| Class A Common Stock | Aug 3, 2026 | M | 6,250 | $2.80 | A | 32,500 | D | |
| Class A Common StockF2 | Aug 3, 2026 | S | 269 | $133.0074 | D | 32,231 | D | |
| Class A Common StockF3 | Aug 3, 2026 | S | 555 | $133.8083 | D | 31,676 | D | |
| Class A Common StockF4 | Aug 3, 2026 | S | 135 | $135.4241 | D | 31,541 | D | |
| Class A Common StockF5 | Aug 3, 2026 | S | 6,354 | $136.4246 | D | 25,187 | D | |
| Class A Common StockF6 | Aug 3, 2026 | S | 9,989 | $137.2456 | D | 15,198 | D | |
| Class A Common StockF7 | Aug 3, 2026 | S | 2,431 | $138.0892 | D | 12,767 | D | |
| Class A Common StockF8 | Aug 3, 2026 | S | 267 | $139.2052 | D | 12,500 | D | |
| Class A Common StockF2 | Aug 3, 2026 | S | 84 | $133.0045 | D | 12,416 | D | |
| Class A Common StockF3 | Aug 3, 2026 | S | 173 | $133.8076 | D | 12,243 | D | |
| Class A Common StockF4 | Aug 3, 2026 | S | 44 | $135.4122 | D | 12,199 | D | |
| Class A Common StockF5 | Aug 3, 2026 | S | 1,981 | $136.4246 | D | 10,218 | D | |
| Class A Common StockF6 | Aug 3, 2026 | S | 3,124 | $137.2453 | D | 7,094 | D | |
| Class A Common StockF7 | Aug 3, 2026 | S | 762 | $138.0897 | D | 6,332 | D | |
| Class A Common StockF8 | Aug 3, 2026 | S | 82 | $139.209 | D | 6,250 | D | |
| Class A Common StockF2 | Aug 3, 2026 | S | 84 | $133.0096 | D | 6,166 | D | |
| Class A Common StockF3 | Aug 3, 2026 | S | 173 | $133.8076 | D | 5,993 | D | |
| Class A Common StockF4 | Aug 3, 2026 | S | 43 | $135.4088 | D | 5,950 | D | |
| Class A Common StockF5 | Aug 3, 2026 | S | 1,983 | $136.424 | D | 3,967 | D | |
| Class A Common StockF6 | Aug 3, 2026 | S | 3,125 | $137.2457 | D | 842 | D | |
| Class A Common StockF7 | Aug 3, 2026 | S | 760 | $138.0901 | D | 82 | D | |
| Class A Common StockF8 | Aug 3, 2026 | S | 82 | $139.2042 | D | 0 | D | |
| Class A Common StockF9 | Aug 3, 2026 | S | 6,250 | $137.37 | D | 168,750 | I | By spouse |
| Class A Common StockF9 | Aug 3, 2026 | S | 6,250 | $137.37 | D | 162,500 | I | By spouse |
Table II — derivative securities
| Security | Conv. / exercise price | Date | Code | Shares | A/D | Exercisable | Expires | Underlying | Underlying shares | Owned after | D/I |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Stock Option (right to buy)F10 | $2.80 | Aug 3, 2026 | M | 20,000 | D | — | Jun 7, 2031 | Class A Common Stock | 20,000 | 555,000 | D |
| Stock Option (right to buy)F10 | $2.80 | Aug 3, 2026 | M | 6,250 | D | — | Jun 7, 2031 | Class A Common Stock | 6,250 | 548,750 | D |
| Stock Option (right to buy)F10 | $2.80 | Aug 3, 2026 | M | 6,250 | D | — | Jun 7, 2031 | Class A Common Stock | 6,250 | 542,500 | D |
Explanation of responses
- F1The 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.
- F10The options are fully vested and exercisable.
- F2The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $132.500 to $133.470 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.
- F3The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $133.510 to $133.9525 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.
- F4The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $134.6675 to $135.650 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.
- F5The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $135.745 to $136.740 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.
- F6The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $136.750 to $137.740 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.
- F7The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $137.750 to $138.740 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.
- F8The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $138.890 to $139.500 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.
- F9Represents shares held by the Reporting Person's spouse.