Zerostack

ZSTK · NASDAQ

$3.71−$0.18 (−4.63%)TodayMarket closed · Oct 20, 4:10 PM ET

Prev close $3.89

Who owns ZSTK

Largest institutional holders, from their latest 13F filings

Top institutional holders of ZSTK
Holder	Shares	% of shares	Change, last filing	Filed
Reis-Faria (Daniel)	5.95M	245.05%	+5.95M	Jul 27, 2026
Heinrich (Michael)	4.61M	189.65%	+4.61M	Jul 27, 2026
Vaiman (Dany)	263.25K	10.83%	+258.87K	Jul 27, 2026
AVF III L.P.	112.99K	4.65%	+0	May 20, 2026
dao5 Capital Fund L.P.	108.00K	4.44%	+0	May 20, 2026
Csapl (Singapore) Holdings Pte. Ltd.	69.76K	2.87%	+0	May 20, 2026
Vanguard Capital Management, LLC	25.44K	1.05%	+0	Jun 30, 2026
Geode Capital Management, L.L.C.	20.99K	0.86%	−4.33K	Jun 30, 2026
Vanguard Fiduciary Trust Co	12.65K	0.52%	+0	Jun 30, 2026
Empery Asset Management, L.P.	8.95K	0.37%	−14.80K	Mar 31, 2025

Largest mutual fund holders

Top mutual fund holders of ZSTK
Holder	Shares	% of shares	Change, last filing	Filed
Vanguard Extended Market Index Fund	25.44K	1.05%	+0	Jul 31, 2026
Fidelity Extended Market Index Fund	13.34K	0.55%	+0	Jul 31, 2026
Fidelity Series Total Market Index Fund	2.28K	0.09%	+0	Jul 31, 2026
Fidelity Total Market Index Fund	1.49K	0.06%	+0	Jul 31, 2026
Fidelity NASDAQ Composite Index Fund	133	0.01%	+0	Jul 31, 2026

Insider trades

Form 4 filings by officers, directors and large holders

Over the last 6 months, insiders bought $3.48M (1 trade) and sold $7.57K (1 trade) of ZSTK on the open market.

Latest ZSTK insider transactions
Insider	Date	Type	Shares	Price	Value
Rong Rudy	Aug 19, 2026	Sale	1.00K	$7.57	$7.57K
Heinrich Michael	Jul 20, 2026	Award	500.00K	—	—
Heinrich Michael	Jul 20, 2026	Buy	4.61M	$0.7549	$3.48M
Reis-Faria Daniel	Jul 20, 2026	Option exercise	5.95M	$25.19	$150.00M
Reis-Faria Daniel	Jul 20, 2026	Award	500.00K	—	—
Reis-Faria Daniel	Jul 20, 2026	Option exercise	5.95M	$0.0001	$595
Vaiman Dany	Jul 20, 2026	Award	250.00K	—	—
WOO EDWARD	May 5, 2026	Award	35.00K	—	—
LEVENTHAL MANFRED	May 5, 2026	Award	35.00K	—	—
Zeifman Laurence	May 5, 2026	Award	28.00K	—	—

Short interest

Settled Sep 30, 2026

Shares short: 97.10K
Days to cover: 1.00
% of shares outstanding: 4.00%
Average daily volume: 129.59K
Change since last report: −22.0%

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