Every Form 4 that One Stop Systems, Inc. (OSS) has filed with the SEC in the last 12 months is listed below, newest first, and each one links through to the document itself with the summary and the scores our analysis gives it.
A Form 4 covers the transactions officers, directors and large holders report, so if you follow OSS and want that one kind of document rather than the whole filing history, this is the page to keep. The company's other filings, of every form, are on the full OSS filings page.
ONE STOP SYSTEMS, INC. (OSS) reported that Chief Executive Officer and director Michael Knowles disposed of shares in two transactions classified as payments of tax liability by delivering or withholding securities. On August 7, 2026 and August 15, 2026, a total of 17,242 shares of common stock were forfeited upon conversion of vested restricted stock units to cover tax withholdings, using the market price at each forfeiture. After these events, Mr. Knowles continued to hold substantial unvested restricted stock units that remain subject to vesting conditions.
ONE STOP SYSTEMS, INC. (OSS) reported that its Chief Financial Officer, Daniel G. Gabel, had 3,832 shares of common stock withheld on August 7, 2026 to pay tax liabilities upon conversion of 11,881 vested restricted stock units into common shares. After this tax-withholding disposition, he holds 150,064 shares directly, including 115,881 unvested restricted stock units that remain subject to vesting conditions. No Rule 10b5-1 trading plan is reported for this transaction.
KNOWLES MICHAEL reported disposition transactions in this Form 4 filing.
ONE STOP SYSTEMS, INC. CEO Michael Knowles reported a routine tax-related share forfeiture tied to vested equity compensation. He forfeited 19,675 shares of common stock at a value of $16.89 per share to cover tax withholdings when 50,000 vested restricted stock units converted into shares.
After this transaction, he directly holds 607,383 shares of common stock, which includes 333,311 unvested restricted stock units that remain subject to vesting conditions. The filing reflects compensation and tax mechanics rather than an open-market purchase or sale decision.
ONE STOP SYSTEMS, INC. Chief Financial Officer Daniel G. Gabel reported a routine tax-related share forfeiture. On conversion of 5,000 vested restricted stock units into common stock, he forfeited 1,613 shares at $15.68 per share to cover tax withholdings.
After this non-market disposition, he directly holds 153,896 shares of common stock and 127,762 unvested restricted stock units that remain subject to vesting conditions. The filing reflects compensation and tax mechanics rather than an open-market purchase or sale.
ONE STOP SYSTEMS, INC. director David George Bassett reported routine equity compensation and a related tax sale of common stock. On May 20, 2026, he acquired 11,984 restricted stock units under the company’s 2017 Equity Incentive Plan in connection with his board service, which are subject to vesting conditions.
A prior grant of 21,000 restricted stock units from May 21, 2025 recently vested and converted into common shares. To cover tax withholdings, 8,000 of those shares were sold in an open-market transaction at $17.64 per share on May 26, 2026, using the market price at the time of sale.
Following these transactions, Bassett holds 24,984 shares of common stock directly and continues to hold 11,984 unvested restricted stock units that remain subject to vesting requirements. The activity reflects standard director stock awards and associated tax-related share sales rather than discretionary open-market buying.
ONE STOP SYSTEMS, INC. director Gregory W. Matz reported a mix of equity compensation and tax-related selling activity. On May 20, he received 11,984 restricted stock units under the company’s 2017 Equity Incentive Plan, which are subject to vesting conditions. On May 26, he sold 8,000 shares of common stock at $17.52 per share after the conversion of 21,000 vested restricted stock units, with the sale used to cover tax withholdings. Following these transactions, he holds 78,914 shares of common stock, including 11,984 unvested restricted stock units that remain subject to vesting.
Dumont Michael J. reported acquisition or exercise transactions in this Form 4 filing.
ONE STOP SYSTEMS, INC. director Michael J. Dumont received a grant of 11,984 restricted stock units of common stock on May 20, 2026 at no cash cost, as compensation for his service as a director under the company’s 2017 Equity Incentive Plan.
After this grant, Dumont holds 119,833 common-share equivalents, consisting of 107,849 shares of common stock and 11,984 unvested restricted stock units that remain subject to vesting conditions.
ONE STOP SYSTEMS, INC. director Mitchell H. Herbets reported both an equity award and a related share sale. He received 11,984 restricted stock units as compensation for his board service, granted under the company’s 2017 Equity Incentive Plan and subject to vesting conditions.
He then sold 5,000 shares of common stock at $17.62 per share, with the footnotes explaining this sale was made to cover tax withholdings after 21,000 vested restricted stock units were converted into shares. Following these transactions, he directly holds 48,984 shares, consisting of 11,984 unvested restricted stock units and 37,000 shares of common stock.
KNOWLES MICHAEL reported acquisition or exercise transactions in this Form 4 filing.
ONE STOP SYSTEMS, INC. Chief Executive Officer Michael Knowles filed an amended insider ownership report to correct a prior clerical error. A previous Form 4 had incorrectly shown a grant of 21,000 restricted stock units on May 21, 2025. The amendment reduces the number of shares reported as beneficially owned following that transaction by 21,000 shares. According to the corrected disclosure, Knowles beneficially owns 627,058 shares as of March 16, 2026, and the amendment does not reflect any change in beneficial ownership other than this reporting adjustment.
ONE STOP SYSTEMS, INC. chief product officer James Ison reported a mix of equity awards, tax withholdings, and gifts involving company common stock. On February 7, 2026, he received a grant of 34,313 restricted stock units under the 2017 Equity Incentive Plan, tied to his ongoing executive service.
That same day, he forfeited 6,546 shares at $9.24 per share to cover tax withholdings upon conversion of vested restricted stock units, and made bona fide gifts of 8,213 shares directly and 8,213 shares to a revocable family trust where he serves as trustee. On February 15, 2026, he forfeited an additional 3,120 shares at $8.70 per share for tax withholdings and gifted 4,263 shares directly and 4,263 shares to the same trust.
After these transactions, he continued to hold OSS common stock both directly and indirectly through the trust, and footnotes state that 125,934 unvested restricted stock units remain subject to vesting conditions.
ONE STOP SYSTEMS, INC. Chief Financial Officer Daniel G. Gabel disposed of 7,799 shares of common stock through a tax-withholding forfeiture. The shares were surrendered when 23,761 vested restricted stock units converted into common shares, with the forfeited amount used to cover tax obligations at the market price.
After this tax-withholding disposition, Gabel directly held 155,509 common shares. He also holds 132,762 unvested restricted stock units that remain subject to vesting conditions, meaning additional shares could be delivered to him over time as those units vest.
KNOWLES MICHAEL reported disposition transactions in this Form 4 filing.
ONE STOP SYSTEMS, INC. Chief Executive Officer Michael Knowles reported tax-related share forfeitures linked to vesting restricted stock units. On February 7, 2026, he forfeited 13,298 shares of common stock, and on February 15, 2026, he forfeited an additional 6,650 shares, both to cover tax withholdings when vested restricted stock units converted into shares. After these transactions, he directly owned 648,058 shares of common stock and also held 404,311 unvested restricted stock units that remain subject to vesting conditions.
One Stop Systems, Inc. (OSS) reported an equity award to its Chief Financial Officer, Daniel G. Gabel. On February 7, 2026, he was granted 55,239 restricted stock units (RSUs) of OSS common stock at a price of $0 per share under the company’s 2017 Equity Incentive Plan.
After this grant, Mr. Gabel beneficially owns 163,308 shares of common stock, which includes 156,523 unvested RSUs that remain subject to vesting conditions. The award was made in connection with his ongoing service on the executive management team.
One Stop Systems, Inc. reported that its Chief Executive Officer and director, Michael Knowles, received an equity award in the form of restricted stock units. On 02/07/2026, he was granted 101,862 restricted stock units under the company’s 2017 Equity Incentive Plan for his ongoing executive service.
These units were recorded at a price of $0 per share, reflecting a compensatory grant rather than an open‑market purchase. After this grant, Knowles beneficially owned 668,006 shares of common stock, including 470,035 unvested restricted stock units that remain subject to vesting conditions.
ONE STOP SYSTEMS, INC. Chief Financial Officer Daniel G. Gabel reported an automatic share withholding related to equity compensation. On December 31, 2025, 3,215 shares of common stock were forfeited to cover tax withholdings when an aggregate 10,000 vested restricted stock units converted into common shares, using the market price of $7.18 per share at the time.
Following this tax-related transaction, Gabel beneficially owned 108,069 shares of common stock directly. This total includes 101,284 unvested restricted stock units that remain subject to vesting conditions, meaning a large portion of his reported holdings is still contingent on future service or performance requirements.
ONE STOP SYSTEMS, INC. CEO Michael Knowles reported a routine tax-related share forfeiture. On 12/31/2025 he forfeited 19,075 shares of common stock at $7.18 per share to cover tax withholdings when an aggregate 50,000 vested restricted stock units converted into common stock.
After this transaction, he beneficially owned 566,144 shares of common stock, including 368,173 unvested restricted stock units that remain subject to vesting conditions. The filing indicates the holdings are reported as directly owned.