15 insiders reported 70 Form 4 transactions for Boundless Bio, Inc. (BOLD) over the past 18 months (most recent 2026-07-21). Recent activity: TANG CAPITAL MANAGEMENT LLC (10% Owner) Buy 265 shares, TANG KEVIN (10% Owner) Buy 265 shares, TANG CAPITAL MANAGEMENT LLC (10% Owner) Buy 1,623 shares, TANG KEVIN (10% Owner) Buy 1,623 shares, TANG CAPITAL MANAGEMENT LLC (10% Owner) Buy 2,975 shares. Source: SEC Form 4.
| Date | Insider | Title | Type | Shares | Value |
|---|---|---|---|---|---|
| 2026-07-21 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 265 | $647 |
| 2026-07-21 | TANG KEVIN | 10% Owner | Buy | 265 | $647 |
| 2026-07-21 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 1,623 | $3,960 |
| 2026-07-21 | TANG KEVIN | 10% Owner | Buy | 1,623 | $3,960 |
| 2026-07-21 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 2,975 | $7,259 |
| 2026-07-21 | TANG KEVIN | 10% Owner | Buy | 2,975 | $7,259 |
| 2026-07-16 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 43,878 | $106,624 |
| 2026-07-16 | TANG KEVIN | 10% Owner | Buy | 43,878 | $106,624 |
| 2026-07-16 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 1,600 | $3,904 |
| 2026-07-16 | TANG KEVIN | 10% Owner | Buy | 1,600 | $3,904 |
| 2026-07-16 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 18,491 | $45,118 |
| 2026-07-16 | TANG KEVIN | 10% Owner | Buy | 18,491 | $45,118 |
| 2026-07-13 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 7 | $17 |
| 2026-07-13 | TANG KEVIN | 10% Owner | Buy | 7 | $17 |
| 2026-07-13 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 43,367 | $105,382 |
| 2026-07-13 | TANG KEVIN | 10% Owner | Buy | 43,367 | $105,382 |
| 2026-07-13 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 48,211 | $116,671 |
| 2026-07-13 | TANG KEVIN | 10% Owner | Buy | 48,211 | $116,671 |
| 2026-07-08 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 27,062 | $67,384 |
| 2026-07-08 | TANG KEVIN | 10% Owner | Buy | 27,062 | $67,384 |
| 2026-07-08 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 15,810 | $39,209 |
| 2026-07-08 | TANG KEVIN | 10% Owner | Buy | 15,810 | $39,209 |
| 2026-07-08 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Buy | 14,338 | $35,271 |
| 2026-07-08 | TANG KEVIN | 10% Owner | Buy | 14,338 | $35,271 |
| 2026-07-06 | ARCH Venture Fund IX Overage, L.P. | 10% Owner | Buy | 16,000 | $16,480 |
Source: SEC Form 4 filings · as of 2026-07-21