Arkolith/Insider Trading/CSTL

CSTL Insider Trading

Name: Arkolith
Brand: Arkolith

Castle Biosciences Inc · full profile →Last filing Jul 14, 2026

Net Selling · 180d

Open-Market Buys (180d)

0 insiders

Open-Market Sells (180d)

$5.5M

5 insiders

Net Insider Flow

-$5.5M

open market, 180d

Reporting Insiders

102 P/S transactions

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Build on these Form 4 transactions

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Recent Form 4 Transactions

100 shown

Date	Insider	Role	Action	Shares	Price	Value
Jul 14, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	550	—	$0
Jul 14, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$22.92	$6K
Jul 14, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$22.92	$6K
Jul 14, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$22.92	$6K
Jul 14, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$22.92	$6K
Jul 14, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	1K	$22.92	$26K
Jul 14, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	1K	$22.92	$31K
Jul 14, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	550	$22.92	$13K
Jul 14, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	550	$2.39	$1K
Jul 1, 2026	Oelschlager Kristen M	Chief Operating Officer	Sell(S)	400	$24.78	$10K
Jul 1, 2026	Oelschlager Kristen M	Chief Operating Officer	Sell(S)	8K	$24.40	$200K
Jul 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	6K	—	$0
Jul 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$24.29	$7K
Jul 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$24.29	$7K
Jul 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$24.29	$7K
Jul 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$24.29	$7K
Jul 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	1K	$24.29	$28K
Jul 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	1K	$24.29	$33K
Jul 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	6K	$24.29	$151K
Jul 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	6K	$2.39	$15K
Jun 16, 2026	Oelschlager Kristen M	Chief Operating Officer	Sell(S)	9K	$20.71	$178K
Jun 15, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	550	—	$0
Jun 15, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$20.66	$6K
Jun 15, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$20.66	$6K
Jun 15, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$20.66	$6K
Jun 15, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$20.66	$6K
Jun 15, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	1K	$20.66	$24K
Jun 15, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	1K	$20.66	$28K
Jun 15, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	550	$20.66	$11K
Jun 15, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	550	$2.39	$1K
Jun 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	6K	—	$0
Jun 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	204	—	$0
Jun 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$20.86	$6K
Jun 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$20.86	$6K
Jun 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$20.86	$6K
Jun 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$20.86	$6K
Jun 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	1K	$20.86	$24K
Jun 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	1K	$20.86	$28K
Jun 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	6K	$20.86	$130K
Jun 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	6K	$2.39	$14K
Jun 1, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	204	$2.39	$488
May 28, 2026	Olson Tiffany	Director	Grant(A)	12K	—	$0
May 28, 2026	Goldberg Ellen	Director	Grant(A)	12K	—	$0
May 28, 2026	Harrison Miles	Director	Grant(A)	12K	—	$0
May 28, 2026	Cotton Rodney	Director	Grant(A)	12K	—	$0
May 28, 2026	Caple Kim	Director	Grant(A)	12K	—	$0
May 28, 2026	Cole G Bradley	Director	Grant(A)	12K	—	$0
May 28, 2026	Bradbury Daniel	Director	Grant(A)	12K	—	$0
May 22, 2026	Cole G Bradley	Director	Option exercise(M)	14K	—	$0
May 22, 2026	Cole G Bradley	Director	Option exercise(M)	14K	—	—
May 22, 2026	Cotton Rodney	Director	Option exercise(M)	14K	—	$0
May 22, 2026	Cotton Rodney	Director	Option exercise(M)	14K	—	—
May 22, 2026	Caple Kim	Director	Option exercise(M)	14K	—	$0
May 22, 2026	Caple Kim	Director	Option exercise(M)	14K	—	—
May 22, 2026	Bradbury Daniel	Director	Option exercise(M)	14K	—	$0
May 22, 2026	Bradbury Daniel	Director	Option exercise(M)	14K	—	—
May 22, 2026	Harrison Miles	Director	Option exercise(M)	14K	—	$0
May 22, 2026	Harrison Miles	Director	Option exercise(M)	14K	—	—
May 22, 2026	Olson Tiffany	Director	Option exercise(M)	14K	—	$0
May 22, 2026	Olson Tiffany	Director	Option exercise(M)	14K	—	—
May 22, 2026	Goldberg Ellen	Director	Option exercise(M)	14K	—	$0
May 22, 2026	Goldberg Ellen	Director	Option exercise(M)	14K	—	—
May 21, 2026	Juvenal Tobin W	Chief Commercial Officer	Option exercise(M)	11K	—	$0
May 21, 2026	Juvenal Tobin W	Chief Commercial Officer	Option exercise(M)	11K	$3.38	$38K
May 21, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	420	—	$0
May 21, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	212	$20.20	$4K
May 21, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	212	$20.20	$4K
May 21, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	212	$20.20	$4K
May 21, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	212	$20.20	$4K
May 21, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	880	$20.20	$18K
May 21, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	1K	$20.20	$21K
May 21, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	420	$20.20	$8K
May 21, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	420	$2.39	$1K
May 20, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	130	—	$0
May 20, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	66	$20.00	$1K
May 20, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	66	$20.00	$1K
May 20, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	66	$20.00	$1K
May 20, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	66	$20.00	$1K
May 20, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	273	$20.00	$5K
May 20, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	322	$20.00	$6K
May 20, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	130	$20.00	$3K
May 20, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	130	$2.39	$311
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	6K	—	$0
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	41	$22.59	$926
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	41	$22.59	$926
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	41	$22.59	$926
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	41	$22.59	$926
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	168	$22.59	$4K
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	198	$22.59	$4K
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	906	$22.59	$20K
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	237	$22.08	$5K
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	237	$22.08	$5K
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	237	$22.08	$5K
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	237	$22.08	$5K
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	985	$22.08	$22K
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	1K	$22.08	$26K
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	5K	$22.08	$117K
May 7, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	6K	$2.39	$15K
Apr 21, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Option exercise(M)	550	—	$0
Apr 21, 2026	Maetzold Derek J	Pres. & Chief Exec. Officer, Director	Sell(S)	278	$25.10	$7K

Data Source

Insider transactions sourced from SEC EDGAR Form 4 filings, normalized within minutes of acceptance. "Buy"/"Sell" mark open-market transactions (codes P/S), the tradeable signal. Awards, option exercises and tax-withholding are shown with their raw code. All data is public domain.

Coverage: Form 4 filings indexed 2021-01-04 → 2026-07-21. Earlier history is backfilling; this window widens as it deepens.

Programmatic access via the Arkolith API & MCP server (insider.transactions, insider.company).