BOLD insiders were on both sides of the trade this year. Buys came to roughly $1.5 million (one buyer), sales to $134,000 (three sellers).
TANG KEVIN (10% Owner) made the biggest buy, worth around $362,000.
Big money check: 40 institutions held BOLD as of Q2 2026, and more funds bought than sold. Quarter by quarter: 2 quarters in a row of net buying by insiders. Insiders bought in 2 of the last 7 full quarters.
| Filed | Insider | Role | Type | Shares | Price | Value | Source |
|---|---|---|---|---|---|---|---|
| Aug 28, 2026 | TANG CAPITAL MANAGEMENT LLC | 10% Owner | Sell | 18,300 | $2.97 | $54K | SEC |
| Jul 21, 2026 | TANG KEVIN | 10% Owner | Buy | 265 | $2.44 | $647 | SEC |
| Jul 21, 2026 | TANG KEVIN | 10% Owner | Buy | 1,623 | $2.44 | $4K | SEC |
| Jul 21, 2026 | TANG KEVIN | 10% Owner | Buy | 2,975 | $2.44 | $7K | SEC |
| Jul 16, 2026 | TANG KEVIN | 10% Owner | Buy | 43,878 | $2.43 | $107K | SEC |
| Jul 16, 2026 | TANG KEVIN | 10% Owner | Buy | 1,600 | $2.44 | $4K | SEC |
| Jul 16, 2026 | TANG KEVIN | 10% Owner | Buy | 18,491 | $2.44 | $45K | SEC |
| Jul 13, 2026 | TANG KEVIN | 10% Owner | Buy | 48,211 | $2.42 | $117K | SEC |
| Jul 13, 2026 | TANG KEVIN | 10% Owner | Buy | 43,367 | $2.43 | $105K | SEC |
| Jul 13, 2026 | TANG KEVIN | 10% Owner | Buy | 7 | $2.48 | $17 | SEC |
| Jul 8, 2026 | TANG KEVIN | 10% Owner | Buy | 27,062 | $2.49 | $67K | SEC |
| Jul 8, 2026 | TANG KEVIN | 10% Owner | Buy | 14,338 | $2.46 | $35K | SEC |
| Jul 8, 2026 | TANG KEVIN | 10% Owner | Buy | 15,810 | $2.48 | $39K | SEC |
| Jul 6, 2026 | GILLIS STEVEN | 10% Owner | Sell | 16,000 | $2.49 | $40K | SEC |
| Jul 6, 2026 | ARCH Venture Partners IX, L.P. | 10% Owner | Sell | 16,000 | $2.49 | $40K | SEC |
In the last 12 months Boundless Bio, Inc. insiders made open-market purchases worth about $1.5 million and sales worth about $134,000. Data comes from SEC Form 4 filings, updated every 30 minutes on CapitalSnitch.
The most recent open-market insider trade in BOLD was filed on 2026-08-28.
40 investment managers reported holding BOLD in SEC Form 13F filings for Q2 2026.
No congressional trades in BOLD were reported in the past two years. The full list is free on CapitalSnitch.
Public-record data for research and education, not investment advice. Insider sales are often pre-planned (10b5-1). Congress data: Data derived from public disclosures filed under the Ethics in Government Act and the STOCK Act, republished free for public transparency and news reporting. Disclosures may lag the trade by 45 days or more and show amounts only as ranges. This data may not be used for credit rating, loan underwriting, solicitation of money (political, charitable or other), direct-mail or commercial targeting (5 U.S.C. 13107).