OSS (One Stop Systems, Inc. Common Stock)

Insider Trading Activity

Every open-market purchase and sale reported by OSS officers, directors and 10%+ beneficial owners on SEC Form 4, which must be filed within two business days of the transaction. Sales often reflect scheduled 10b5-1 plans or tax withholding rather than a directional view, so read counts alongside the size and the filer.

Market data may be delayed, incomplete, or inaccurate. Not a recommendation to buy, sell, or hold any security. Verify quotes with your broker before trading. See Terms §17.

Form 4 Filings
50
most recent
Open-Market Buys
1
code P
Sales
0
code S
Reporting Insiders
22
current holders
OSS — Recent Form 4 Transactions (latest 2026-09-04)
FiledInsiderRole TypeSharesValue
2026-09-04 Daniel G. Gabel Chief Financial Officer F
2026-09-04 MICHAEL KNOWLES Chief Executive Officer F
2026-06-12 MICHAEL KNOWLES Chief Executive Officer F
2026-05-28 Daniel G. Gabel Chief Financial Officer F
2026-05-26 DAVID GEORGE BASSETT Director MIXED
2026-05-26 Gregory W Matz Director MIXED
2026-05-26 Michael J. Dumont Director A
2026-05-26 Mitchell H Herbets Director MIXED
2026-03-27 MICHAEL KNOWLES Chief Executive Officer A
2026-03-02 MICHAEL KNOWLES Chief Executive Officer F
2026-03-02 James Ison CPO MIXED
2026-03-02 Daniel G. Gabel Chief Financial Officer F
2026-02-11 Daniel G. Gabel Chief Financial Officer A
2026-02-11 MICHAEL KNOWLES Chief Executive Officer A
2026-01-12 Daniel G. Gabel Chief Financial Officer F
2026-01-07 MICHAEL KNOWLES Chief Executive Officer F
2025-09-02 MICHAEL KNOWLES Chief Executive Officer MIXED
2025-08-25 James Ison CPO MIXED
2025-05-28 Mitchell H Herbets Director A
2025-05-27 Michael J. Dumont Director F
2025-05-23 Gregory W Matz Director A
2025-03-13 James Ison CPO MIXED
2025-03-05 Daniel G. Gabel Chief Financial Officer A
2025-02-24 James Ison CPO A
2024-12-30 MICHAEL KNOWLES Chief Executive Officer F
2024-11-12 Daniel G. Gabel Chief Financial Officer A
2024-09-25 John W Morrison Jr. Chief Financial Officer F
2024-09-25 James Ison CPO MIXED
2024-08-21 John W Morrison Jr. Chief Financial Officer F
2024-08-21 James Ison CPO MIXED
2024-08-15 Joseph M. Manko Jr. Director Buy
2024-07-11 KENNETH F POTASHNER Director M
2024-07-03 KENNETH F POTASHNER Director A
2024-07-03 Michael J. Dumont Director A
2024-07-03 James Ison CPO A
2024-07-03 John W Morrison Jr. Chief Financial Officer A
2024-07-03 Mitchell H Herbets Director A
2024-07-03 Gioia Messinger Director A
2024-07-03 Gregory W Matz Director A
2024-07-03 MICHAEL KNOWLES Chief Executive Officer A
2024-07-03 Joseph M. Manko Jr. Director A
2024-06-18 MICHAEL KNOWLES Chief Executive Officer F
2024-05-28 John W Morrison Jr. Chief Financial Officer F
2024-05-28 James Ison CPO MIXED
2024-04-03 KENNETH F POTASHNER Director M
2024-04-03 DAVID RAUN Director M
2024-03-27 John W Morrison Jr. Chief Financial Officer F
2024-03-27 James Ison CPO MIXED
2024-02-07 John W Morrison Jr. Chief Financial Officer F
2024-02-07 James Ison CPO MIXED
OSS — Current Insider Holders
InsiderRole Shares HeldValue
10%+ Owner 4,854,593
10%+ Owner 2,988,113
Director 1,271,249
Director 1,195,899
VP of Sales 1,079,312
Chief Executive Officer 590,141
President and CEO 425,597
Director 398,601
CPO 367,962
Chief Financial Officer 305,381
Managing Director, Bressner 216,260
Director 206,682
Director 199,236
Director 180,673
Chief Financial Officer 150,064
Director 92,435
Director 89,414
Director 49,690
Director 48,984
Director 39,266
Director 29,930
Director 24,984
How to read Form 4 activity

Form 4 reports a change in beneficial ownership by an officer, director or 10%+ holder, and must be filed within two business days of the transaction — so this is close to real time, unlike the 45-day-lagged 13F institutional data.

Transaction codes matter more than the raw buy/sell count. Code P is an open-market purchase — an insider choosing to buy with their own money, which is the signal most research treats as informative. Code S is a sale, but sales are frequently pre-scheduled under a 10b5-1 plan or cover tax withholding on vesting equity, so a run of sales often says nothing directional. Codes A and M are grants and option exercises rather than open-market decisions.

Full filing history and per-insider positions are on the OSS quote page; the site-wide leaderboard is on the insider transactions hub.