ZeroStack ZSTK Insider Ownership

NASDAQ ZSTK
$4.24 -0.07 (-1.51%)
At close: Sep 9, 2026 · 4:00 PM EDT

Insider Holdings by Owner

9.77Mn Shares

Insider Ownership Statistics

as of 30 Sep, 2026
Insider Ownership
809.07%
Shares Held by Insiders
5.95Mn
filed for Sep 2026
Shares Outstanding
736.00K
736,000 shares
Direct Holdings
5.95Mn
Indirect: 0
Net Shares Traded (QoQ)
0
no net change in Sep 2026
Insiders Holding Shares
12
with Form 4 holdings on file

Shares Owned by Insiders

Shares held % of outstanding
Latest
Average ownership
Peak ownership

Shares Purchased/Sold by Insiders

Bought Sold
Latest quarter
Net over range
Buying quarters
Form 4 Holdings

Insiders Holding ZSTK

Insiders 12
Shares held 9.77Mn
Of outstanding 1,327.78%
# Insider Position Direct Indirect Total Share of Insiders Last Filed
1 Daniel Reis-Faria Ceo 5,954,743 0 5,954,743 60.9% 20 Jul, 2026
2 Juan Carlos Gomez Roa Director 2,042,509 0 2,042,509 20.9% 21 Mar, 2023
3 Clifford Starke Ceo 906,846 0 906,846 9.3% 16 Dec, 2024
4 Marc Mastronardi Director 160,000 0 160,000 1.6% 21 Mar, 2023
5 Beverley Richardson Director 150,000 0 150,000 1.5% 21 Mar, 2023
6 John Timothy Leslie Director 138,574 0 138,574 1.4% 21 Mar, 2023
7 Edward Woo Director 134,698 0 134,698 1.4% 16 Dec, 2024
8 Kevin Taylor Chairman 124,186 0 124,186 1.3% 14 Nov, 2023
9 Brandon Konigsberg Director 100,000 0 100,000 1.0% 21 Mar, 2023
10 Thomas Solomon Director 35,766 0 35,766 0.4% 15 Nov, 2023
11 Harold Wolkin Director 25,000 0 25,000 0.3% 11 Sep, 2024
12 Sammy Dorf Executive Chairman 107 0 107 0.0% 16 Dec, 2024

Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.

Form 4 Filings

110 Insider Transactions

Source SEC Form 4
Latest quarter Sep 2026
Download Data
Date Insider Position Transaction Shares Price Value Shares Held After Ownership
19 Aug, 2026 Rudy Rong President Disposed S 1,000 $7.57 $7.57K 0 Direct
20 Jul, 2026 Dany Vaiman Cfo Acquired A 250,000 $0.00 $0 250,000 Direct
20 Jul, 2026 Daniel Reis-Faria Ceo Acquired X 5,954,743 $0.00 $595 5,954,743 Direct
20 Jul, 2026 Daniel Reis-Faria Ceo Acquired A 500,000 $0.00 $0 500,000 Direct
20 Jul, 2026 Daniel Reis-Faria Ceo Disposed X 5,954,743 $25.19 $150.00Mn 0 Direct
05 May, 2026 Edward Woo Director Acquired A 35,000 $0.00 $0 35,000 Direct
05 May, 2026 Manfred Leventhal Director Acquired A 35,000 $0.00 $0 35,000 Direct
05 May, 2026 Laurence Zeifman Director Acquired A 28,000 $0.00 $0 28,000 Direct
31 Mar, 2026 Michael Heinrich Executive Chairman Disposed J 4,902,220 0 Indirect
22 Oct, 2025 Michael John Brown Director Acquired A 7,468 $0.00 $0 94,421 Direct
30 Jun, 2025 Clifford Starke Ceo Disposed D 1,028,665 0 Direct
30 Jun, 2025 Harold Wolkin Director Disposed D 30,000 0 Direct
30 Jun, 2025 Harold Wolkin Director Disposed D 30,000 0 Direct
30 Jun, 2025 Manfred Leventhal Director Disposed D 5,000 0 Direct
30 Jun, 2025 Harold Wolkin Director Disposed D 30,000 0 Direct
30 Jun, 2025 Clifford Starke Ceo Disposed D 1,028,665 0 Direct
30 Jun, 2025 Clifford Starke Ceo Disposed D 1,028,665 0 Direct
30 Jun, 2025 Clifford Starke Ceo Disposed D 1,028,665 0 Direct
30 Jun, 2025 Harold Wolkin Director Disposed D 30,000 0 Direct
30 Jun, 2025 Harold Wolkin Director Acquired A 30,000 30,000 Direct