Boundless Bio, Inc. Insider Trading Activity
Every SEC Form 4 insider transaction reported for Boundless Bio, Inc. (BOLD), sourced directly from SEC EDGAR and updated as new filings are accepted.
By Trabud · Insider-trading data from SEC EDGAR
Latest filing:
Compiled automatically from SEC EDGAR Form 4 filings and refreshed daily. Figures count purchases (code P) and sales (code S) only — not grants, option exercises, or gifts. How this page is built. Not investment advice.
Quick Answer
Are BOLD insiders buying or selling?
In the last 12 months, Boundless Bio, Inc. insiders reported 6 open-market purchases ($1.5M) and 3 sales ($134.0K) — net buying of $1.4M. Since April 2024, Trabud has recorded 13 Form 4 filings for BOLD: 10 buys ($16.1M) and 3 sells ($134.0K).
Source: SEC EDGAR Form 4
What stands out
- The largest open-market purchase in the last 12 months was $714.8K by Kevin Tang (10% Owner) on Jun 29, 2026. SEC ↗
- The most recent open-market purchase was reported on Jul 21, 2026 (2 months ago).
Key Statistics (April 2024 – Aug 28, 2026)
Total Form 4 filings
13
SEC EDGAR
Insider filers
5
Insider buys (10)
$16.1M
Insider sells (3)
$134.0K
Insider sentiment
Net buyingNet insider flow of $16.0M in net buying since April 2024, and $1.4M in net buying over the last 12 months. 1 insider buy in the last 90 days.
Recent BOLD insider transactions
| Date | Insider | Role | Type | Shares | Price | Value | Filing |
|---|---|---|---|---|---|---|---|
| Aug 28, 2026 | TANG KEVIN | 10% Owner | Sale | 18.3K | $2.97 | $54.4K | SEC ↗ |
| Jul 21, 2026 | Kevin Tang | 10% Owner | Purchase | 4.9K | $2.44 | $11.9K | SEC ↗ |
| Jul 17, 2026 | Kevin Tang | 10% Owner | Purchase | 64.0K | $2.43 | $155.6K | SEC ↗ |
| Jul 13, 2026 | Kevin Tang | 10% Owner | Purchase | 91.6K | $2.42 | $222.1K | SEC ↗ |
| Jul 9, 2026 | Kevin Tang | 10% Owner | Purchase | 57.2K | $2.48 | $141.9K | SEC ↗ |
| Jul 6, 2026 | Keith Crandell | 10% Owner | Sale | 16.0K | $2.49 | $39.8K | SEC ↗ |
| Jul 6, 2026 | ARCH Venture Fund IX, L.P. | 10% Owner | Sale | 16.0K | $2.49 | $39.8K | SEC ↗ |
| Jul 2, 2026 | Kevin Tang | 10% Owner | Purchase | 107.5K | $2.50 | $268.9K | SEC ↗ |
| Jun 29, 2026 | Kevin Tang | 10% Owner | Purchase | 286.3K | $2.50 | $714.8K | SEC ↗ |
| Apr 4, 2024 | Kristina Burow | Director, 10% Owner | Purchase | 200.0K | $16.00 | $3.2M | SEC ↗ |
| Apr 4, 2024 | Keith Crandell | 10% Owner | Purchase | 200.0K | $16.00 | $3.2M | SEC ↗ |
| Apr 4, 2024 | ARCH Venture Fund IX, L.P. | 10% Owner | Purchase | 200.0K | $16.00 | $3.2M | SEC ↗ |
| Apr 4, 2024 | Peter Kolchinsky | 10% Owner | Purchase | 312.5K | $16.00 | $5.0M | SEC ↗ |
Showing the 13 most recent of 13 Form 4 filings for Boundless Bio, Inc..
Most active BOLD insiders
- Kevin Tang7 filings
- ARCH Venture Fund IX, L.P.2 filings
- Keith Crandell2 filings
- Kristina Burow1 filing
- Peter Kolchinsky1 filing
Ask anything about BOLD insider activity
Use Trabud's AI agent to query Boundless Bio, Inc.'s Form 4 history in plain English — "Show me BOLD CEO purchases this year" or compare it against any other ticker.
Open the AI agentBOLD insider trading FAQ
Are Boundless Bio, Inc. insiders buying or selling?
In the last 12 months, Boundless Bio, Inc. insiders reported 6 open-market purchases ($1.5M) and 3 sales ($134.0K) — net buying of $1.4M. Since April 2024, Trabud has recorded 13 Form 4 filings for BOLD: 10 buys ($16.1M) and 3 sells ($134.0K). Over the full record that is net buying of $16.0M.
How many insiders trade BOLD stock?
5 distinct insider filers — officers, directors, 10%+ owners, and investment groups filing jointly — have reported Form 4 transactions for Boundless Bio, Inc.. The most recent filing was accepted on Aug 28, 2026.
Where does Trabud get BOLD insider trading data?
All BOLD insider trading data comes directly from official SEC EDGAR Form 4 filings, which corporate insiders must submit within two business days of a transaction under Section 16(a) of the Securities Exchange Act of 1934.