Castle Biosciences, Inc. (CSTL) Institutional Ownership & Insider Trading

176 institutions reported holding Castle Biosciences, Inc. shares in 13F filings for the quarter ended 2026-06-30, according to EquiReason's reading of their SEC filings. 183 insider trades on Form 4 since 2025-10-01.

Source: SEC EDGAR filings · figures as of 2026-06-30 · read by EquiReason

CSTLCastle Biosciences, Inc.Follow CSTL — free

Diagnostics & Research · Healthcare

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Market cap: 1.0B
P/E TTM: —
Dividend yield: 0.0%
52-week: —
Next earnings: 5 Nov, in 12 days

Institutions · all 13F filers

quarter to 30 Jun 2026 · filers in both quarters

176 institutions held 89.5% of the shares. Across filers that reported both quarters, shares held changed -1.2%.

Largest moves, shares (millions)

Institutional flow by quarter

net shares added or trimmed, millions · filers in both quarters

Quarter	Holders	Shares held, M	Change	Increased	New	Decreased	Closed
Jun 26	176	27	-1.2%	71	17	53	23
Mar 26	186	28	+1.0%	68	19	52	33
Dec 25	193	27	+3.0%	59	35	62	14
Sep 25	169	27	+0.2%	51	30	50	10
Jun 25	152	27	+3.0%	63	12	43	39
Mar 25	178	26	-3.0%	71	24	48	38
Dec 24	194	26	+2.4%	59	34	61	24
Sep 24	184	26	+1.1%	71	39	46	14

Castle Biosciences, Inc. — questions

Who owns Castle Biosciences, Inc. stock?: 176 institutions reported Castle Biosciences, Inc. shares in 13F filings for the quarter ended 2026-06-30. The largest: BlackRock, Inc. (10.8%), RTW INVESTMENTS, LP (9.1%), PRINCIPAL FINANCIAL GROUP INC (5.7%).
Are Castle Biosciences, Inc. insiders buying or selling?: 183 insider trades on Form 4 since 2025-10-01; the full list, with dates, people and plan status, is on this page.

Every figure on this page comes from Castle Biosciences, Inc.'s own SEC filings — see them on SEC EDGAR. Price data is licensed and shown only inside the product.

How these figures are read: methodology · EquiReason.

Important information. Figures on this page are taken from filings submitted to the U.S. Securities and Exchange Commission (SEC) and processed automatically by EquiReason. They may contain errors, omissions or delays, and EquiReason makes no representation or warranty as to their accuracy, completeness or timeliness. Always verify figures against the original filing on SEC EDGAR before relying on them.

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