Cooper Revocable Trust dated April 25, 2001

SEC source: 0001209191-20-049268 · doc4.xml · nonDerivative · entry 3

Cooper Steve D · CIK 0001729851 · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,042,675

F3 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust.

SEC source: 0001209191-20-049268 · doc4.xml · nonDerivative · entry 2

Cooper Steve D · CIK 0001729851 · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,052,675

F3 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust.

SEC source: 0001209191-20-049268 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,062,675

F1 · price: The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $2.60 to $2.80 per share, inclusive.

F2 · price: The reporting person undertakes to provide One Stop Systems, Inc., any security holder of One Stop Systems, Inc., or the staff of the Securities and Exchange Commission, upon request, the full information regarding the number of shares sold at each separate price within the range set forth in footnote (1) to this Form 4.

F3 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust.

SEC source: 0001209191-20-048123 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,090,425

F1 · price: The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $2.50 to $2.60 per share, inclusive.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust.

SEC source: 0001209191-20-038764 · doc4.xml · nonDerivative · entry 2

Cooper Steve D · CIK 0001729851 · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,102,675

F2 · price: The reporting person undertakes to provide One Stop Systems, Inc., any security holder of One Stop Systems, Inc., or the staff of the Securities and Exchange Commission, upon request, the full information regarding the number of shares sold at each separate price within the range set forth in footnotes (1) and (4) to this Form 4.

F4 · price: The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $2.15 to $2.52 per share, inclusive.

F3 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is a former officer and director of the issuer.

SEC source: 0001209191-20-038764 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,181,014

F1 · price: The price reported in column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $1.90 to $2.00 per share, inclusive.

F2 · price: The reporting person undertakes to provide One Stop Systems, Inc., any security holder of One Stop Systems, Inc., or the staff of the Securities and Exchange Commission, upon request, the full information regarding the number of shares sold at each separate price within the range set forth in footnotes (1) and (4) to this Form 4.

F3 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is a former officer and director of the issuer.

SEC source: 0001209191-20-020415 · doc4.xml · derivative · entry 5

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,750

Underlying: Common Stock · 3,750 shares

Expires not disclosed

F11 · shares: The Reporting Person's Form 4 filed on February 18, 2020, reported in Footnote 10 that 3,750 shares of common stock underlying the option to purchase common stock failed to vest and were canceled as a result of the Reporting Person's service to the Company having ceased as of February 15, 2020. However, pursuant to the terms of the Reporting Person's Employment Agreement with the Company, 3,750 shares of common stock underlying the option to purchase common stock accelerated and became fully vested and exercisable upon the Reporting Person's subsequent execution of a Waiver and Release.

F12 · derivative.exercise_date: The option is exercisable as it vests. 1/3 of the shares subject to the option will vest on April 18, 2018, and 1/12th of the total number of shares subject to the option vest quarterly thereafter, subject to the reporting person's continued service to the issuer through each such vesting date.

F12 · derivative.expiration_date: The option is exercisable as it vests. 1/3 of the shares subject to the option will vest on April 18, 2018, and 1/12th of the total number of shares subject to the option vest quarterly thereafter, subject to the reporting person's continued service to the issuer through each such vesting date.

SEC source: 0001209191-20-020415 · doc4.xml · derivative · entry 4

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 10,000 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F8 · shares: The Reporting Person's Form 4 filed on February 18, 2020, reported in Footnote 13 that 20,000 shares of common stock underlying the restricted stock units failed to vest and were canceled as a result of the Reporting Person's service to the Company having ceased as of February 15, 2020. However, pursuant to the terms of the Reporting Person's Employment Agreement with the Company, 10,000 of the 20,000 shares of common stock underlying the restricted stock units accelerated and became fully vested and exercisable upon the Reporting Person's subsequent execution of a Waiver and Release.

F9 · derivative.exercise_date: On February 13, 2019, the reporting person was granted 30,000 restricted stock units. Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/6, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each six month period of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/6. This Restricted stock unit will be fully vested after three (3) years of service. The Initial Vesting Date shall be six months following the Date of Restricted stock unit Grant.

F9 · derivative.expiration_date: On February 13, 2019, the reporting person was granted 30,000 restricted stock units. Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/6, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each six month period of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/6. This Restricted stock unit will be fully vested after three (3) years of service. The Initial Vesting Date shall be six months following the Date of Restricted stock unit Grant.

F10 · balance_after: On February 15, 2020, the Reporting Person's service as an employee to the Company ceased and, as such, 10,000 shares of common stock underlying the restricted stock units failed to vest and were cancelled.

SEC source: 0001209191-20-020415 · doc4.xml · derivative · entry 3

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 10,000 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F5 · shares: The Reporting Person's Form 4 filed on February 18, 2020, reported in Footnote 12 that 12,500 shares of common stock underlying the restricted stock units failed to vest and were canceled as a result of the Reporting Person's service to the Company having ceased as of February 15, 2020. However, pursuant to the terms of the Reporting Person's Employment Agreement with the Company, 10,000 of the 12,500 shares of common stock underlying the restricted stock units accelerated and became fully vested and exercisable upon the Reporting Person's subsequent execution of a Waiver and Release.

F6 · derivative.exercise_date: On April 11, 2018, the reporting person was granted 30,000 restricted stock units. Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/12, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each quarter of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/12. This Restricted stock unit will be fully vested after three (3) years of service. The Initial Vesting Date shall be one quarter following the Date of Restricted stock unit Grant.

F6 · derivative.expiration_date: On April 11, 2018, the reporting person was granted 30,000 restricted stock units. Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/12, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each quarter of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/12. This Restricted stock unit will be fully vested after three (3) years of service. The Initial Vesting Date shall be one quarter following the Date of Restricted stock unit Grant.

F7 · balance_after: On February 15, 2020, the Reporting Person's service as an employee to the Company ceased and, as such, 2,500 shares of common stock underlying the restricted stock units failed to vest and were cancelled.

SEC source: 0001209191-20-020415 · doc4.xml · nonDerivative · entry 2

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,212,675

F3 · kind: Represents a "net stock issuance" of vested and outstanding restricted stock units. The reporting person received 6,935 shares of common stock on the net stock issuance of 10,000 shares of common stock. The reporting person forfeited 3,065 shares of common stock underlying the vested and outstanding restricted Stock Units to cover tax withholdings, using the closing stock price on March 12, 2020 of $1.56.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is a director of the issuer.

SEC source: 0001209191-20-020415 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,205,740

F1 · kind: Represents a "net stock issuance" of vested and outstanding restricted stock units. The reporting person received 6,935 shares of common stock on the net stock issuance of 10,000 shares of common stock. The reporting person forfeited 3,065 shares of common stock underlying the vested and outstanding restricted Stock Units to cover tax withholdings, using the closing stock price on March 12, 2020 of $1.56.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is a director of the issuer.

SEC source: 0001209191-20-010049 · doc4.xml · derivative · entry 14

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 2,500 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F11 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F13 · derivative.exercise_date: On February 13, 2019, the reporting person was granted 30,000 restricted stock units. Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/6, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each six month period of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/6. This Restricted stock unit will be fully vested after three (3) years of service. The Initial Vesting Date shall be six months following the Date of Restricted stock unit Grant. On February 15, 2020, the reporting person's service as an employee to the Company ceased and, as such, 20,000 shares of common stock underlying this restricted stock unit failed to vest and were cancelled.

F13 · derivative.expiration_date: On February 13, 2019, the reporting person was granted 30,000 restricted stock units. Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/6, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each six month period of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/6. This Restricted stock unit will be fully vested after three (3) years of service. The Initial Vesting Date shall be six months following the Date of Restricted stock unit Grant. On February 15, 2020, the reporting person's service as an employee to the Company ceased and, as such, 20,000 shares of common stock underlying this restricted stock unit failed to vest and were cancelled.

SEC source: 0001209191-20-010049 · doc4.xml · derivative · entry 13

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 2,500 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F11 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F12 · derivative.exercise_date: On April 11, 2018, the reporting person was granted 30,000 restricted stock units. Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/12, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each quarter of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/12. This Restricted stock unit will be fully vested after three (3) years of service. The Initial Vesting Date shall be one quarter following the Date of Restricted stock unit Grant. On February 15, 2020, the reporting person's service as an employee to the Company ceased and, as such, 12,500 shares of common stock underlying this restricted stock unit failed to vest and were cancelled.

F12 · derivative.expiration_date: On April 11, 2018, the reporting person was granted 30,000 restricted stock units. Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/12, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each quarter of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/12. This Restricted stock unit will be fully vested after three (3) years of service. The Initial Vesting Date shall be one quarter following the Date of Restricted stock unit Grant. On February 15, 2020, the reporting person's service as an employee to the Company ceased and, as such, 12,500 shares of common stock underlying this restricted stock unit failed to vest and were cancelled.

SEC source: 0001209191-20-010049 · doc4.xml · derivative · entry 12

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 41,250 shares

Expires 2027-04-17

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F10 · derivative.exercise_date: The option is exercisable as it vests. 1/3 of the shares subject to the option will vest on April 18, 2018, and 1/12th of the total number of shares subject to the option vest quarterly thereafter, subject to the reporting person's continued service to the issuer through each such vesting date. On February 15, 2020, the reporting person's service as an employee to the Company ceased and, as such, 3,750 shares of common stock underlying this option to purchase common stock failed to vest and were cancelled.

SEC source: 0001209191-20-010049 · doc4.xml · derivative · entry 11

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 90,000 shares

Expires 2026-04-01

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F9 · derivative.exercise_date: The option is fully vested.

SEC source: 0001209191-20-010049 · doc4.xml · derivative · entry 10

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 100,000 shares

Expires 2022-01-17

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F9 · derivative.exercise_date: The option is fully vested.

SEC source: 0001209191-20-010049 · doc4.xml · derivative · entry 9

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 200,000 shares

Expires 2021-12-06

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F9 · derivative.exercise_date: The option is fully vested.

SEC source: 0001209191-20-010049 · doc4.xml · derivative · entry 8

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 180,000 shares

Expires 2024-07-15

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F9 · derivative.exercise_date: The option is fully vested.

SEC source: 0001209191-20-010049 · doc4.xml · nonDerivative · entry 7

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,198,805

F8 · kind: Represents a "net stock issuance" of vested and outstanding restricted stock units. The reporting person received 3,246 shares of common stock on the net stock issuance of 5,000 shares of common stock. The reporting person forfeited 1,754 shares of common stock underlying the vested and outstanding Restricted stock units to cover tax withholdings, using the closing stock price on February 13, 2020 of $2.73.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is a director of the issuer.

SEC source: 0001209191-20-010049 · doc4.xml · nonDerivative · entry 6

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,195,559

F7 · kind: Represents a "net stock issuance" of vested and outstanding restricted stock units. The reporting person received 1,810 shares of common stock on the net stock issuance of 2,500 shares of common stock. The reporting person forfeited 690 shares of common stock underlying the vested and outstanding restricted Stock Units to cover tax withholdings, using the closing stock price on February 13, 2020 of $2.73.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is a director of the issuer.

SEC source: 0001209191-20-010049 · doc4.xml · nonDerivative · entry 5

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,193,749

F6 · kind: Represents a "net exercise" of outstanding stock options. The reporting person received 5,424 shares of common stock on net exercise of option to purchase 41,250 shares of common stock. The reporting person forfeited 35,826 shares of common stock underlying the option in payment of the exercise price and to cover tax withholdings, using the closing stock price on February 13, 2020 of $2.73.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is a director of the issuer.

SEC source: 0001209191-20-010049 · doc4.xml · nonDerivative · entry 4

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,188,325

F5 · kind: Represents a "net exercise" of outstanding stock options. The reporting person received 26,648 shares of common stock on net exercise of option to purchase 90,000 shares of common stock. The reporting person forfeited 63,352 shares of common stock underlying the option in payment of the exercise price and to cover tax withholdings, using the closing stock price on February 13, 2020 of $2.73.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is a director of the issuer.

SEC source: 0001209191-20-010049 · doc4.xml · nonDerivative · entry 3

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,161,677

F4 · kind: Represents a "net exercise" of outstanding stock options. The reporting person received 33,690 shares of common stock on net exercise of option to purchase 100,000 shares of common stock. The reporting person forfeited 66,310 shares of common stock underlying the option in payment of the exercise price and to cover tax withholdings, using the closing stock price on February 13, 2020 of $2.73.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is a director of the issuer.

SEC source: 0001209191-20-010049 · doc4.xml · nonDerivative · entry 2

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,127,987

F3 · kind: Represents a "net exercise" of outstanding stock options. The reporting person received 67,314 shares of common stock on net exercise of option to purchase 200,000 shares of common stock. The reporting person forfeited 132,686 shares of common stock underlying the option in payment of the exercise price and to cover tax withholdings, using the closing stock price on February 13, 2020 of $2.73.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is a director of the issuer.

SEC source: 0001209191-20-010049 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · Director · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 3,060,673

F1 · kind: Represents a "net exercise" of outstanding stock options. The reporting person received 70,593 shares of common stock on net exercise of option to purchase 180,000 shares of common stock. The reporting person forfeited 109,407 shares of common stock underlying the option in payment of the exercise price and to cover tax withholdings, using the closing stock price on February 13, 2020 of $2.73.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is a director of the issuer.

SEC source: 0001209191-19-050728 · doc4.xml · derivative · entry 2

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 15,000

Underlying: Common Stock · 2,500 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F3 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F4 · derivative.exercise_date: Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/12, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each quarter of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/12. This Restricted Stock Unit will be fully vested after three (3) years of service.

F4 · derivative.expiration_date: Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/12, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each quarter of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/12. This Restricted Stock Unit will be fully vested after three (3) years of service.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.

SEC source: 0001209191-19-050728 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 2,990,080

F1 · kind: Represents a "net stock issuance" of vested and outstanding Restricted Stock Units. The reporting person received 1,967 shares of common stock on the net stock issuance of 2,500 shares of common stock. The reporting person forfeited 533 shares of common stock underlying the vested and outstanding Restricted Stock Units to cover tax withholdings, using the closing stock price on September 19, 2019 of $2.68.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.

SEC source: 0001209191-19-047068 · doc4.xml · derivative · entry 4

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 17,500

Underlying: Common Stock · 2,500 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F6 · derivative.exercise_date: Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/12, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each quarter of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/12. This Restricted Stock Unit will be fully vested after three (3) years of service.

F6 · derivative.expiration_date: Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/12, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each quarter of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/12. This Restricted Stock Unit will be fully vested after three (3) years of service.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.

SEC source: 0001209191-19-047068 · doc4.xml · derivative · entry 3

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 25,000

Underlying: Common Stock · 5,000 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F4 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F5 · derivative.exercise_date: Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/6, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each six month period of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/6. This Restricted Stock Unit will be fully vested after three (3) years of service. The Initial Vesting Date shall be six months following the Date of Restricted Stock Unit Grant.

F5 · derivative.expiration_date: Prior to the Initial Vesting Date, the Vested Ratio shall be zero. On the Initial Vesting Date, the Vested Ratio shall be 1/6, provided the Grantee's service has not been terminated prior to the Initial Vesting Date. For each six month period of Grantee service from the Initial Vesting Date until the Vested Ratio equals 1/1, the Vested Ratio shall be increased by 1/6. This Restricted Stock Unit will be fully vested after three (3) years of service. The Initial Vesting Date shall be six months following the Date of Restricted Stock Unit Grant.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.

SEC source: 0001209191-19-047068 · doc4.xml · nonDerivative · entry 2

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 2,988,113

F3 · kind: Represents a "net stock issuance" of vested and outstanding Restricted Stock Units. The reporting person received 2,159 shares of common stock on the net stock issuance of 2,500 shares of common stock. The reporting person forfeited 341 shares of common stock underlying the vested and outstanding Restricted Stock Units to cover tax withholdings, using the closing stock price on August 12, 2019 of $1.65.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.

SEC source: 0001209191-19-047068 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 2,985,954

F1 · kind: Represents a "net stock issuance" of vested and outstanding Restricted Stock Units. The reporting person received 3,803 shares of common stock on the net stock issuance of 5,000 shares of common stock. The reporting person forfeited 1,197 shares of common stock underlying the vested and outstanding Restricted Stock Units to cover tax withholdings, using the closing stock price on August 12, 2019 of $1.65.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.

SEC source: 0001209191-19-036034 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 2,982,151

F1 · price: The price reported in column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $1.725 to $1.7399 per share, inclusive.

F2 · price: The reporting person undertakes to provide One Stop Systems, Inc., any security holder of One Stop Systems, Inc., or the staff of the Securities and Exchange Commission, upon request, the full information regarding the number of shares purchased at each separate price within the ranges set forth in footnote (1) to this Form 4.

F3 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.

SEC source: 0001209191-19-032827 · doc4.xml · derivative · entry 2

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 100,000 shares

Expires 2019-05-13

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F3 · derivative.exercise_date: The option is fully vested.

SEC source: 0001209191-19-032827 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 2,967,151

F1 · kind: Represents a "net exercise" of outstanding stock options. The reporting person received 33,485 shares of common stock on net exercise of option to purchase 100,000 shares of common stock. The reporting person forfeited 66,515 shares of common stock underlying the option in payment of the exercise price and to cover tax withholdings, using the closing stock price on May 8, 2019 of $2.38.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.

SEC source: 0001209191-19-024649 · doc4.xml · derivative · entry 3

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 20,000

Underlying: Common Stock · 5,000 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Restricted stock units convert into common stock on a one-for-one basis.

F3 · derivative.exercise_date: On April 11, 2018, the reporting person was granted 30,000 restricted stock units, vesting in twelve equal quarterly installments beginning the first quarter after the grant date.

F3 · derivative.expiration_date: On April 11, 2018, the reporting person was granted 30,000 restricted stock units, vesting in twelve equal quarterly installments beginning the first quarter after the grant date.

SEC source: 0001209191-19-024649 · doc4.xml · nonDerivative · entry 2

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By trust

Disclosed balance after: 2,933,666

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.

SEC source: 0001209191-19-024649 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By trust

Disclosed balance after: 2,935,394

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Restricted stock units convert into common stock on a one-for-one basis.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.

SEC source: 0001209191-18-019432 · doc4.xml · derivative · entry 2

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 100,000 shares

Expires 2018-03-31

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

SEC source: 0001209191-18-019432 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By Trust

Disclosed balance after: 2,926,696

F1 · kind: Represents a "net exercise" of outstanding stock options. The reporting person received 38,580 shares of common stock on net exercise of option to purchase 100,000 shares of common stock. The reporting person forfeited 16,393 shares of common stock underlying the option in payment of the exercise price and 45,027 shares of common stock to cover tax withholdings, using the closing stock price on March 9, 2018 of $6.10.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.

SEC source: 0001209191-18-008990 · doc4.xml · nonDerivative · entry 1

Cooper Steve D · CIK 0001729851 · Director · President, CEO · 10% owner

Cooper Revocable Trust dated April 25, 2001 · CIK 0001729938 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · By trust

Disclosed balance after: 2,888,116

F1 · shares: On February 9, 2018, the underwriters of One Stop Systems' initial public offering (the "IPO") partially exercised their over-allotment option to purchase 100,000 shares of common stock from the Cooper Revocable Trust, dated April 25, 2001. The transaction closed on February 9, 2018. The underwriters still have an option to purchase up to an additional 185,000 shares of common stock from the trust to cover additional over-allotments, if any.

F2 · ownership.nature: These shares are owned directly by the Cooper Revocable Trust dated April 25, 2001, a ten percent owner of the issuer, and indirectly by Steve Cooper as trustee of the trust. Steve Cooper is an officer and director of the issuer.