CSTL | CASTLE BIOSCI | Owners

S&P 500$7,666.45
+0.19%
2m
DOW 30$50,926.56
+0.04%
2m
NASDAQ 100$30,501.56
+0.31%
2m
Russell 2000$279.02
+0.41%
2m
Russell 1000$416.97
+0.20%
2m
S&P 400$3,633.16
+1.03%
2m
S&P 600$1,665.65
+0.65%
2m

CASTLE BIOSCI (CSTL)

NASDAQ

$35.58+$0.32 (+0.91%)

Price as of Oct 02, 2026 4:15 PM EDT

$1.1B
Market Cap
58.59%
1-Year Change
Diagnostics & Research
Industry

Top Holders

Institutional

Mutual Funds

Holder	Ownership %	Shares Held	Change (Shares, %)	Report Date
BLACKROCK, INC.	10.78%	3.3M	+309,017 (+9.39%)	Jun 30, 2026
WASATCH ADVISORS INC	10.55%	3.2M	-122,185 (-3.79%)	Dec 31, 2022
BLACKROCK INC.	9.97%	3.0M	+449,286 (+14.76%)	Jun 30, 2024
BLACKROCK FUNDING, INC. /DE	9.56%	2.9M	-198,963 (-6.81%)	Dec 31, 2024
RTW INVESTMENTS, LP	9.09%	2.8M	+20,000 (+0.72%)	Jun 30, 2026
VANGUARD GROUP INC	7.20%	2.2M	+27,511 (+1.25%)	Dec 31, 2025
PRINCIPAL FINANCIAL GROUP INC	5.65%	1.7M	-43,229 (-2.50%)	Jun 30, 2026

Holder	Ownership %	Shares Held	Change (Shares, %)	Report Date
VANGUARD INDEX FUNDS	3.91%	1.2M	+45,820 (+3.83%)	Jun 30, 2026
PRINCIPAL FUNDS, INC.	2.38%	727,106	+17,956 (+2.47%)	Jul 31, 2026
IVY FUNDS	1.56%	477,630	0 (0.00%)	Jun 30, 2026
AIM INTERNATIONAL MUTUAL FUNDS (INVESCO INTERNATIONAL MUTUAL FUNDS)	1.41%	430,219	0 (0.00%)	Jul 31, 2026
DFA INVESTMENT DIMENSIONS GROUP INC	1.40%	428,855	-83,620 (-19.50%)	Jul 31, 2026
MUTUAL FUND SERIES TRUST	1.26%	386,425	0 (0.00%)	Jun 30, 2026
FIDELITY SALEM STREET TRUST	1.09%	333,048	+291,156 (+87.42%)	Jul 31, 2026

Current Ownership Distribution

Institutions472.3M (75.06%)
Mutual Funds152.9M (24.31%)
Insiders3.9M (0.63%)
Other0 (0.00%)

Insider Transactions

0.63% (3.9M)
Current InsiderOwnership (%, shares)
0
Number of InsiderBuying (last 12 months)
$0.00
Amount of InsiderBuying (last 12 months)
4
Number of InsiderSelling (last 12 months)
$98.6M
Amount of InsiderSelling (last 12 months)

Insider Name & Title	Type	Date	Transaction Value	Shares	Share Price	Shares After Transactions
Juvenal Tobin W Chief Commercial Officer	Sell	Sep 30, 2026	$35,362.80	1,034	$34.20	52,007
Juvenal Tobin W Chief Commercial Officer	Sell	Sep 29, 2026	$196,765.41	5,543	$35.50	53,041
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Exempt	Sep 21, 2026	$0.00	8,580	$0.00	8,165
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Exempt	Sep 21, 2026	$20,506.20	8,580	$2.39	30,059
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Sep 21, 2026	$303,165.72	8,580	$35.33	21,479
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Sep 21, 2026	$112,998.13	3,198	$35.33	11,236
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Sep 21, 2026	$96,037.81	2,718	$35.33	9,550
Juvenal Tobin W Chief Commercial Officer	Sell	Sep 15, 2026	$115,757.75	3,294	$35.14	58,584
Juvenal Tobin W Chief Commercial Officer	Sell	Sep 14, 2026	$106,863.14	3,306	$32.32	61,878
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Exempt	Sep 11, 2026	$0.00	8,584	$0.00	16,745
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Exempt	Sep 11, 2026	$20,515.76	8,584	$2.39	30,063
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Sep 11, 2026	$267,552.00	8,361	$32.00	21,702
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Sep 11, 2026	$99,968.00	3,124	$32.00	14,517
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Sep 11, 2026	$84,992.00	2,656	$32.00	12,339
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Sep 11, 2026	$7,309.94	223	$32.78	21,479
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Sep 11, 2026	$2,720.74	83	$32.78	14,434
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Sep 11, 2026	$2,327.38	71	$32.78	12,268
Oelschlager Kristen M Chief Operating Officer	Exempt	Sep 01, 2026	$0.00	4,152	$0.00	12,458
Oelschlager Kristen M Chief Operating Officer	Exempt	Sep 01, 2026	$14,033.76	4,152	$3.38	17,508
Oelschlager Kristen M Chief Operating Officer	Sell	Sep 01, 2026	$131,838.72	3,952	$33.36	13,556
Oelschlager Kristen M Chief Operating Officer	Sell	Sep 01, 2026	$6,804.00	200	$34.02	13,356
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Exempt	Aug 28, 2026	$0.00	12,428	$0.00	25,329
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Exempt	Aug 28, 2026	$29,702.92	12,428	$2.39	33,907
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Aug 28, 2026	$380,182.08	11,472	$33.14	22,435
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Aug 28, 2026	$83,015.70	2,505	$33.14	17,850
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Aug 28, 2026	$70,555.06	2,129	$33.14	15,172
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Aug 28, 2026	$8,516.98	257	$33.14	11,277
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Aug 28, 2026	$8,516.98	257	$33.14	11,277
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Aug 28, 2026	$8,516.98	257	$33.14	11,277
MAETZOLD DEREK J Pres. & Chief Exec. Officer	Sell	Aug 28, 2026	$8,516.98	257	$33.14	11,277