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Security record · archived quarter

CSTL

Castle Biosciences, Inc. · Healthcare · Medical - Diagnostics & Research

33.70 -2.1% mkt cap $1.03B quote delayed (FMP) · as of Oct 12 14:08 UTC — separate from filing data below

Q2 2026 Q1 2026 Q4 2025 Q3 2025 Q2 2025 Q1 2025 Q4 2024 Q3 2024
8Tracked holders
—Δ holders
1.95MShares held
$42.47MReported value
+0New positions
−0Exits
— How these are computed → Explain this at the Research Desk →

All ownership figures: tracked 13F managers only, common-stock positions, reporting period Q2 2024

Ownership over time
QuarterHoldersΔSharesReported valueNewExits
Q2 2026 76 -1 16.83M $401.45M +6 −6
Q1 2026 79 -9 16.13M $395.93M +4 −13
Q4 2025 87 +2 17.12M $665.58M +2 —
Q3 2025 16 0 9.41M $214.29M +1 −1
Q2 2025 13 -1 9.39M $191.81M — −1
Q1 2025 11 0 4.13M $82.76M +1 −1
Q4 2024 11 +2 4.84M $128.97M +4 −2
Q3 2024 8 0 2.64M $75.25M — —
Q2 2024 8 — 1.95M $42.47M — —
Holder count
Who holds it · Q2 2024
#ManagerSharesΔ sharesValueTheir weightHeld
1 Citadel Advisors ✦ 693.38K — $15.09M 0.0% n/c 1 SEC ↗
2 Geode Capital Management ✦ (passive) 617.68K — $13.45M 0.0% n/c 1 SEC ↗ ×2
3 Renaissance Technologies ✦ 301.50K — $6.56M 0.0% n/c 1 SEC ↗
4 Marshall Wace ✦ 212.04K — $4.62M 0.0% n/c 1 SEC ↗
5 Point72 Asset Management ✦ 53.78K — $1.17M 0.0% n/c 1 SEC ↗
6 Millennium Management ✦ 34.83K — $758,184 0.0% n/c 1 SEC ↗
7 T. Rowe Price ✦ 20.65K — $450,000 0.0% n/c 1 SEC ↗
8 Two Sigma Investments ✦ 16.80K — $365,736 0.0% n/c 1 SEC ↗

“Their weight” = the position's share of that manager's reported 13F equity value — the conviction measure. ✦ = curated manager.

New buyers

No new tracked buyers this quarter.

Exited

No tracked exits this quarter.

Full-market context: across ALL 13F filers (SEC structured data, Q1 2026): 186 holders, 27.52M shares, $653.08M reported. This is a different, older period than the tracked-universe figures above and the two are never mixed.

Frequently co-owned

What else this security's tracked holders most often hold — shared-ownership counts, not fundamental relationships.

Insider transactions

Open-market purchases (P)

No open-market insider purchases in our coverage window.

Open-market sales (S)

Oct 05 MAETZOLD DEREK J

Officer, Director · 3.20K sh · $113,740

Oct 05 MAETZOLD DEREK J

Officer, Director · 8.58K sh · $305,156

Oct 05 MAETZOLD DEREK J

Officer, Director · 2.72K sh · $96,668

Oct 01 Oelschlager Kristen M

Officer · 1.35K sh · $48,967

Oct 01 Oelschlager Kristen M

Officer · 2.81K sh · $100,350

Sep 30 Juvenal Tobin W

Officer · 1.03K sh · $35,363

Sep 29 Juvenal Tobin W

Officer · 5.54K sh · $196,765

Sep 21 MAETZOLD DEREK J

Officer, Director · 8.58K sh · $303,166

Sep 21 MAETZOLD DEREK J

Officer, Director · 2.72K sh · $96,038

Sep 21 MAETZOLD DEREK J

Officer, Director · 3.20K sh · $112,998

Awards, exercises and tax withholding are never counted as buys or sales here. Methodology

Provenance: Ownership from parsed 13F common-stock positions (tracked universe, comparable sets for changes); insider rows from Forms 3/4/5; stakes from Schedules 13D/13G; every filing links to its original on SEC EDGAR. Reporting period: Q2 2024 · Methodology · Get this via the API