Form 4 for BLLN BillionToOne, Inc.
Accepted 2026-09-21 19:00:11 ET · period of report 2026-09-17 · accession 0002070849-26-000069 · SEC index · Original document
Summary rows
Aggregated the way they appear in lists: one row per insider, transaction code and security table.
| X | Filed | Traded | Ticker | Insider | Title | Type | Price | Qty | Owned | ΔOwn | Value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| DMT | 2026-09-21 19:00 | 2026-09-17 | BLLN | Lynch Thomas P. | See Remarks | M - OptEx | $13.61 | +35.1K | 35.8K | +5,016% | +$477.9K |
| DMT | 2026-09-21 19:00 | 2026-09-17 | BLLN | Lynch Thomas P. | See Remarks | S - Sale+OE | $110.33 | -35.1K | 700 | -98% | -$3.87M |
| DMT | 2026-09-21 19:00 | 2026-09-17 | BLLN | Lynch Thomas P. | See Remarks | M - OptEx | $13.61 | -35.1K | 30.8K | -53% | -$477.9K |
Purchase Sale Sale after option exercise All abbreviations
Every reported transaction
| # | Table | Security | Date | Code | A/D | Shares | Price | Owned after | Own | Exercise / expiry | Underlying | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Common | Class A Common Stock | 2026-09-17 | M | A | 19,384 | $8.65 | 20,084 | D | — | — | (F1) The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 8, 2026. |
| 2 | Common | Class A Common Stock | 2026-09-17 | M | A | 6,968 | $11.55 | 27,052 | D | — | — | (F1) The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 8, 2026. |
| 3 | Common | Class A Common Stock | 2026-09-17 | M | A | 2,920 | $17.12 | 29,972 | D | — | — | (F1) The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 8, 2026. |
| 4 | Common | Class A Common Stock | 2026-09-17 | M | A | 5,840 | $30.78 | 35,812 | D | — | — | (F1) The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 8, 2026. |
| 5 | Common | Class A Common Stock | 2026-09-17 | S | D | 19,384 | $110.36 | 16,428 | D | — | — | (F1) The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 8, 2026. (F2) The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $110.000 to $110.970 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. |
| 6 | Common | Class A Common Stock | 2026-09-17 | S | D | 6,968 | $110.30 | 9,460 | D | — | — | (F1) The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 8, 2026. (F3) The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $110.000 to $110.890 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. |
| 7 | Common | Class A Common Stock | 2026-09-17 | S | D | 2,920 | $110.31 | 6,540 | D | — | — | (F1) The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 8, 2026. (F3) The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $110.000 to $110.890 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. |
| 8 | Common | Class A Common Stock | 2026-09-17 | S | D | 5,840 | $110.29 | 700 | D | — | — | (F1) The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 8, 2026. (F2) The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $110.000 to $110.970 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. |
| 9 | Derivative | Stock Option (right to buy) | 2026-09-17 | M | D | 19,384 | $8.65 | 48,974 | D | $8.65 · — to 2033-01-18 | 19,384 Class A Common Stock | (F4) The options are fully vested and exercisable. The terms of the underlying option grant are as previously reported on the Reporting Person's Form 3 filed on November 5, 2025. |
| 10 | Derivative | Stock Option (right to buy) | 2026-09-17 | M | D | 6,968 | $11.55 | 4,063 | D | $11.55 · — to 2033-10-17 | 6,968 Class A Common Stock | (F4) The options are fully vested and exercisable. The terms of the underlying option grant are as previously reported on the Reporting Person's Form 3 filed on November 5, 2025. |
| 11 | Derivative | Stock Option (right to buy) | 2026-09-17 | M | D | 2,920 | $17.12 | 5,417 | D | $17.12 · — to 2034-10-16 | 2,920 Class A Common Stock | (F4) The options are fully vested and exercisable. The terms of the underlying option grant are as previously reported on the Reporting Person's Form 3 filed on November 5, 2025. |
| 12 | Derivative | Stock Option (right to buy) | 2026-09-17 | M | D | 5,840 | $30.78 | 30,834 | D | $30.78 · — to 2035-09-30 | 5,840 Class A Common Stock | (F4) The options are fully vested and exercisable. The terms of the underlying option grant are as previously reported on the Reporting Person's Form 3 filed on November 5, 2025. |