Skip to main content

ZeroStack Corp.

ZSTK
Exchange
Nasdaq
Industry
Finance Services
SEC CIK
0001790169

In the last 90 days, ZeroStack Corp. insiders filed 1 open-market purchase and 1 sale; 11 institutions reported holding it in 13F filings for Q2 2026, worth $183.8K in total; no superinvestor holds it.

Holders of 5% or more of ZSTK

Holders whose latest Schedule 13D or 13G filing reports 5% or more of ZeroStack Corp., largest stake first. The change is against the holder's previous filing.

Holders of 5% or more of ZSTK
HolderLatest formStakeChangeFirst filedLatest filingFiling
Reis-Faria Daniel13D/A88.30%6.43M shares−1.00 ppfrom 89.30%Oct 10, 20252 filingsDec 23, 2025SEC
Heinrich Michael13D/A86.40%5.37M shares−0.60 ppfrom 87.00%Oct 27, 20252 filingsDec 23, 2025SEC
Reis-Faria Daniel13D/A37.50%6.93M shares–Jul 21, 20261 filingJul 21, 2026SEC
Heinrich Michael13D/A30.20%5.58M shares+20.20 ppfrom 10.00%Apr 2, 20262 filingsJul 21, 2026SEC
Vaiman Dany13D/A23.80%263.2K shares+19.00 ppfrom 4.80%Sep 12, 20244 filingsDec 23, 2025SEC
Starke Clifford13D/A17.10%3.85M shares–Jan 6, 20237 filingsJul 21, 2025SEC
Blockcat Pte. Ltd.13G8.30%1.75M sharesNewSep 4, 20261 filingSep 4, 2026SEC
Puple AI Inc.13G8.30%1.75M sharesNewSep 2, 20261 filingSep 2, 2026SEC

Stakes are as of each holder's latest filing. Holders whose last filing was in the old format (before December 18, 2024) have no stake on record and are not listed, and after an acquisition or delisting holders usually stop filing.

13D and 13G filings

29 Schedule 13D and 13G filings on ZeroStack Corp., newest first, including old-format filings without a stake.

Schedule 13D and 13G filings on ZSTK
Filed (ET)FilerFormStakeChangeEvent dateFiling
Sep 4, 20263:06 PM ETBlockcat Pte. Ltd.13G8.30%1.75M sharesNewAug 19, 2026SEC
Sep 2, 20264:54 PM ETPuple AI Inc.13G8.30%1.75M sharesNewAug 19, 2026SEC
Jul 21, 20265:02 PM ETReis-Faria Daniel13D/A37.50%6.93M shares–Jul 20, 2026SEC
Jul 21, 20264:59 PM ETVaiman Dany13D/A2.90%513.2K shares–Below 5%Jul 20, 2026SEC
Jul 21, 20264:56 PM ETHeinrich Michaeland 1 other13D/A30.20%5.58M shares+20.20 ppfrom 10.00%Jul 20, 2026SEC
Apr 2, 20268:05 PM ETHeinrich Michaeland 1 other13D/A10.00%471.2K shares–Mar 31, 2026SEC
Dec 23, 202510:26 AM ETHeinrich Michaeland 1 other13D/A86.40%5.37M shares−0.60 ppfrom 87.00%Dec 19, 2025SEC
Dec 23, 202510:17 AM ETVaiman Dany13D/A23.80%263.2K shares+19.00 ppfrom 4.80%Dec 19, 2025SEC
Dec 23, 202510:07 AM ETReis-Faria Daniel13D/A88.30%6.43M shares−1.00 ppfrom 89.30%Dec 19, 2025SEC
Oct 27, 20258:15 AM ETHeinrich Michaeland 1 other13D87.00%4.90M sharesNewOct 23, 2025SEC
Oct 10, 20251:23 PM ETReis-Faria Daniel13D89.30%5.95M sharesNewOct 9, 2025SEC
Aug 14, 20254:07 PM ETHighbridge Capital Management LLC13G/A4.40%1.04M shares−0.70 ppfrom 5.10%Below 5%Jun 30, 2025SEC
Jul 21, 20251:09 PM ETStarke Clifford13D/A17.10%3.85M shares–May 9, 2025SEC
Jul 21, 202512:59 PM ETVaiman Dany13D/A4.80%1.08M shares–Below 5%May 9, 2025SEC
May 2, 20254:10 PM ETHighbridge Capital Management LLC13G5.10%1.04M sharesNewMar 31, 2025SEC
Apr 29, 20259:00 AM ETEmpery Asset Management, LPand 2 others13G/A1.92%374.1K shares−3.44 ppfrom 5.36%Below 5%Mar 31, 2025SEC
Jan 21, 20259:30 AM ETEmpery Asset Management, LPand 2 others13G5.36%926.4K sharesNewDec 31, 2024SEC
Dec 17, 2024Starke Clifford13D/AOld format–––SEC
Dec 17, 2024Vaiman Dany13D/AOld format–––SEC
Nov 14, 2024Global X Management CO LLC13G/AOld format–––SEC
Sep 12, 2024Vaiman Dany13DOld format–New–SEC
Sep 11, 2024Starke Clifford13D/AOld format–––SEC
Jun 27, 2024RDS Private Capital II, LP13GOld format–New–SEC
Apr 15, 2024Starke Clifford13D/AOld format–––SEC
Feb 14, 2024Global X Management CO LLC13GOld format–––SEC
Dec 8, 2023Global X Management CO LLC13GOld format–New–SEC
Nov 15, 2023Starke Clifford13D/AOld format–––SEC
Apr 21, 2023Starke Clifford13D/AOld format–––SEC
Jan 6, 2023Starke Clifford13DOld format–New–SEC

Form 144: proposed insider sales

1 notice from officers, directors and other affiliates planning to sell ZeroStack Corp. shares, newest first.

Form 144 notices for ZSTK
Filed (ET)SellerShares to sellMarket valuePlanned saleBrokerFiling
May 22, 20234:01 PM ETMerchan LuisAffiliate500.0K$130.0KMay 22, 2023CHARLES SCHWAB CORPORATIONSEC