Company · Ownership research

CASTLE BIOSCIENCES INC CSTL

CIK 0001447362 · CUSIP 14843C105

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 14843C105 (CSTL), not CUSIP 14843C905 (CSTL), CUSIP 14843C955 (CSTL), and does not merge CUSIPs.

This page lists the top 20 of 74 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	PRINCIPAL FINANCIAL GROUP INC CIK 1126328 · View history	$53.33M 1,500,897 shares	0.03%	-225.75K(-13.10%)Reduced	SEC filing ↗ Nov 2, 2026	▾
02	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$28.21M 793,904 shares	0.00%	-2.01K(-0.30%)Reduced	SEC filing ↗ Nov 6, 2026	▾
03	DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history	$24.59M 692,104 shares	0.00%	-98.98K(-12.50%)Reduced	SEC filing ↗ Nov 4, 2026	▾
04	Jefferies Financial Group Inc. CIK 96223 · View history	$23.00M 647,391 shares	0.31%	0(0.00%)Unchanged	SEC filing ↗ Nov 5, 2026	▾
05	MACKENZIE FINANCIAL CORP CIK 919859 · View history	$20.20M 568,440 shares	0.02%	-225.07K(-28.40%)Reduced	SEC filing ↗ Nov 2, 2026	▾
06	WASATCH ADVISORS LP CIK 814133 · View history	$9.93M 279,343 shares	0.07%	-6(0.00%)Reduced	SEC filing ↗ Oct 13, 2026	▾
07	KORNITZER CAPITAL MANAGEMENT INC /KS CIK 898358 · View history	$9.41M 264,806 shares	0.20%	+571(+0.20%)Added	SEC filing ↗ Nov 3, 2026	▾
08	Allspring Global Investments Holdings, LLC CIK 1890906 · View history	$8.70M 244,962 shares	0.01%	-47.51K(-16.20%)Reduced	SEC filing ↗ Nov 4, 2026	▾
09	Bank of New York Mellon Corp CIK 1390777 · View history	$3.24M 91,310 shares	0.00%	-6.71K(-6.80%)Reduced	SEC filing ↗ Nov 5, 2026	▾
10	PERKINS CAPITAL MANAGEMENT INC CIK 884300 · View history	$1.75M 49,315 shares	1.25%	+33.17K(+205.50%)Added	SEC filing ↗ Nov 2, 2026	▾
11	BARCLAYS PLC CIK 312069 · View history	$1.34M 37,747 shares	0.00%	+7.42K(+24.50%)Added	SEC filing ↗ Nov 6, 2026	▾
12	KBC Group NV CIK 1411133 · View history	$1.28M 36,042 shares	0.00%	0(0.00%)Unchanged	SEC filing ↗ Oct 22, 2026	▾
13	STRS OHIO CIK 820478 · View history	$1.09M 30,700 shares	0.00%	+200(+0.70%)Added	SEC filing ↗ Oct 30, 2026	▾
14	Russell Investments Group, Ltd. CIK 1692234 · View history	$996.98K 28,290 shares	0.00%	-3.39K(-10.70%)Reduced	SEC filing ↗ Nov 6, 2026	▾
15	DEUTSCHE BANK AG\ CIK 948046 · View history	$986.60K 27,768 shares	0.00%	-2.37K(-7.90%)Reduced	SEC filing ↗ Nov 6, 2026	▾
16	HARBOR CAPITAL ADVISORS, INC. CIK 1039128 · View history	$926.00K 26,072 shares	0.06%	-5.68K(-17.90%)Reduced	SEC filing ↗ Oct 22, 2026	▾
17	TRUIST FINANCIAL CORP CIK 92230 · View history	$833.75K 23,466 shares	0.00%	-320(-1.30%)Reduced	SEC filing ↗ Oct 30, 2026	▾
18	First Bank & Trust CIK 1692632 · View history	$652.90K 18,376 shares	0.10%	-215(-1.20%)Reduced	SEC filing ↗ Oct 19, 2026	▾
19	Inspire Investing, LLC CIK 1670139 · View history	$638.76K 17,978 shares	0.03%	-11.07K(-38.10%)Reduced	SEC filing ↗ Oct 22, 2026	▾
20	Creative Planning CIK 1540235 · View history	$621.46K 17,491 shares	0.00%	+3.81K(+27.80%)Added	SEC filing ↗ Nov 2, 2026	▾

Showing 20 / 74 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

Cancelled or null records excluded

Disclosed shares

5,632,554

Not deduplicated across managers

Disclosed value

$200.04M

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

CASTLE BIOSCIENCES INC · Q3 2026

Explore all 74 reporting institutions.

This page includes 20 of 74 reporting institutions. Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

Download CSV
Earlier quarters
Advanced screening & filtering
API & AI access

Already have an account?

＋ New accounts get free API credits to explore data beyond ownership filings.

For AI agents & developers

The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. This page lists 20 of 74 reporting institutions; totals use the complete disclosed data.

Without an account: the last 3 years, with the row caps stated on the page. A free account opens all history on file on these pages and the CSV of what a page shows. Rows beyond the caps and bulk retrieval go through the authenticated API / MCP / CLI.

MCP  https://api.akkrudata.ai/mcp

akkru_institutional_holdings
{"action":"holders","cusip":"14843C105","quarter":"2026Q3","type":"positions","page_size":100}

Connect to MCP with OAuth and follow the returned pagination. Credits and usage limits depend on the account.

MCP endpoint: https://api.akkrudata.ai/mcp
API / MCP / CLI documentation: /documents
llms.txt: /llms.txt

Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.