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BOLD insider buying

1 cluster buy

Boundless Bio, Inc.

When two or more insiders at Boundless Bio, Inc. buy BOLD on the open market around the same time, that clustered conviction is one of the highest-signal patterns in SEC filing data. Below is every cluster we've detected in BOLD plus the full record of qualifying open-market buys, each parsed directly from Form 4 filings and linked back to the source on SEC EDGAR.

Clusters
1
Distinct insiders
5
Total bought
$16.0M
Market cap
$55.7M

Detected clusters

  • Apr 2 – Apr 2, 2024
    Detected Apr 2, 2024
    4 insiders
    Total bought
    $14.6M
    Market cap
    $55.7M

All notable open-market buys in BOLD

Every open-market Form 4 purchase, newest first. Click an insider to see their full buying record across companies.

DateInsiderSharesPriceValueFiling
Jul 21, 2026
TANG KEVIN
10% Owner
2,975$2.44$7.3KSEC ↗
Jul 20, 2026
TANG KEVIN
10% Owner
1,623$2.44$4.0KSEC ↗
Jul 17, 2026
TANG KEVIN
10% Owner
265$2.44$646.6SEC ↗
Jul 16, 2026
TANG KEVIN
10% Owner
18,491$2.44$45.1KSEC ↗
Jul 15, 2026
TANG KEVIN
10% Owner
1,600$2.44$3.9KSEC ↗
Jul 14, 2026
TANG KEVIN
10% Owner
43,878$2.43$106.6KSEC ↗
Jul 13, 2026
TANG KEVIN
10% Owner
48,211$2.42$116.7KSEC ↗
Jul 10, 2026
TANG KEVIN
10% Owner
43,367$2.43$105.4KSEC ↗
Jul 9, 2026
TANG KEVIN
10% Owner
7$2.48$17.4SEC ↗
Jul 8, 2026
TANG KEVIN
10% Owner
14,338$2.46$35.3KSEC ↗
Jul 7, 2026
TANG KEVIN
10% Owner
15,810$2.48$39.2KSEC ↗
Jul 6, 2026
TANG KEVIN
10% Owner
27,062$2.49$67.4KSEC ↗
Jul 1, 2026
TANG KEVIN
10% Owner
71,612$2.49$178.3KSEC ↗
Jun 29, 2026
TANG KEVIN
10% Owner
63,985$2.47$158.0KSEC ↗
Jun 26, 2026
TANG KEVIN
10% Owner
75,047$2.55$191.4KSEC ↗
Jun 25, 2026
TANG KEVIN
10% Owner
145,880$2.48$361.8KSEC ↗
Apr 2, 2024
Kolchinsky Petercluster
10% Owner
296,875$16.00$4.8MSEC ↗
Apr 2, 2024
GILLIS STEVENcluster
10% Owner
133,333$16.00$2.1MSEC ↗
Apr 2, 2024
ARCH Venture Partners IX, LLCcluster
10% Owner
133,333$16.00$2.1MSEC ↗
Apr 2, 2024
Burow Kristinacluster
Director, 10% Owner
133,333$16.00$2.1MSEC ↗
Apr 2, 2024
ARCH Venture Partners IX, LLCcluster
10% Owner
66,667$16.00$1.1MSEC ↗
Apr 2, 2024
GILLIS STEVENcluster
10% Owner
66,667$16.00$1.1MSEC ↗
Apr 2, 2024
Burow Kristinacluster
Director, 10% Owner
66,667$16.00$1.1MSEC ↗
Apr 2, 2024
Kolchinsky Petercluster
10% Owner
15,625$16.00$250.0KSEC ↗

BOLD insider buying — FAQ

Are insiders buying BOLD stock?
Yes — 5 distinct insiders have bought BOLD (Boundless Bio, Inc.) on the open market, including 1 cluster buy where two or more insiders bought within a rolling window. The most recent qualifying activity was Jul 21, 2026.
How much BOLD stock have insiders bought?
Insiders have bought a combined $16.0M of BOLD across 24 open-market purchases, based on SEC Form 4 filings.
What is an insider cluster buy in BOLD?
A cluster buy is two or more distinct Boundless Bio, Inc. insiders — officers, directors, or 10% owners — each buying BOLD on the open market within a rolling window. BOLD has 1 detected cluster buy to date.
Where does this BOLD insider trading data come from?
Every figure is parsed directly from SEC Form 4 filings on EDGAR, and each purchase on this page links back to its original filing document.

How we track insider buying in BOLD

We continuously poll SEC EDGAR for new Form 4 filings and parse every open-market purchase (transaction code P). A cluster is recorded when two or more distinct insiders — officers, directors, or 10% owners — each buy BOLD within a rolling window. We track clusters at every company size, from micro-caps to mega-caps. Every figure on this page traces back to an official filing; open any row to jump straight to the source document. What counts as a cluster buy?

This page is informational and reflects public filing data. It is not investment advice or a recommendation regarding BOLD.