ONE STOP SYSTEMS, INC. — Director's Dealing 2025

Sep 2, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: ONE STOP SYSTEMS, INC. (OSS)
CIK: 0001394056
Period of Report: 2025-02-07

Reporting Person: KNOWLES MICHAEL (N/A)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-02-07	Common Stock	A	131448	$4.06	Acquired	608453	Direct
2025-02-20	Common Stock	F	16800	$3.76	Disposed	591653	Direct
2025-05-21	Common Stock	A	21000	—	Acquired	612653	Direct
2025-06-05	Common Stock	F	19075	$3.06	Disposed	593578	Direct
2025-08-20	Common Stock	F	8359	$5.26	Disposed	585219	Direct

Footnotes

F1: Represents 131,448 restricted stock units granted to the Reporting Person under the Company's 2017 Equity Incentive Plan (the "Plan") in connection with the Reporting Person's ongoing service of the executive management team.

F2: Includes 512,898 unvested restriced stock units held by the Reporting Person, all of which remain subject to certain vesting conditions.

F3: The Reporting Person forfeited 16,800 shares of common stock upon conversion of an aggregate 43,816 vested and outstanding restricted stock units into shares of common stock to cover tax withholdings, using the market price of the issuer's common stock at the time of forfeiture. These restricted stock units were part of the grant reported in Table I of the Form 4 filed by the Reporting Person with the Securities and Exchange Commission on June 6, 2023.

F4: Includes 469,082 unvested restricted stock units held by the Reporting Person, all of which remain subject to certain vesting conditions.

F5: Represents 21,000 restricted stock units granted to the Reporting Person under the Company's 2017 Equity Incentive Plan (the "Plan") in connection with the Reporting Person's ongoing service of the executive management team.

F6: Includes 490,082 unvested restriced stock units held by the Reporting Person, all of which remain subject to certain vesting conditions.

F7: The Reporting Person forfeited 19,075 shares of common stock upon conversion of an aggregate 50,000 vested and outstanding restricted stock units into shares of common stock to cover tax withholdings, using the market price of the issuer's common stock at the time of forfeiture. These restricted stock units were part of the grant reported in Table I of the Form 4 filed by the Reporting Person with the Securities and Exchange Commission on June 6, 2023.

F8: Includes 440,082 unvested restricted stock units held by the Reporting Person, all of which remain subject to certain vesting conditions.

F9: The Reporting Person forfeited 8,359 shares of common stock upon conversion of an aggregate 21,909 vested and outstanding restricted stock units into shares of common stock to cover tax withholdings, using the market price of the issuer's common stock at the time of forfeiture. These restricted stock units were part of the grant reported in Table I of the Form 4 filed by the Reporting Person with the Securities and Exchange Commission on June 6, 2023.

F10: Includes 418,173 unvested restricted stock units held by the Reporting Person, all of which remain subject to certain vesting conditions.