FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
Cooper Steve D
  2. Issuer Name and Ticker or Trading Symbol
ONE STOP SYSTEMS, INC. [OSS]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director __X__ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
President, CEO
(Last)
(First)
(Middle)
2235 ENTERPRISE STREET #110, 
3. Date of Earliest Transaction (Month/Day/Year)
09/20/2019
(Street)

ESCONDIDO, CA 92029
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 09/20/2019   F(1)   1,967 A $ 2.68 2,990,080 I By Trust (2)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Restricted Stock Unit (3) 09/20/2019   M     2,500   (4)   (4) Common Stock 2,500 $ 0 15,000 I By Trust (2)

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Cooper Steve D
2235 ENTERPRISE STREET #110
ESCONDIDO, CA 92029
  X   X   President, CEO  
Cooper Revocable Trust dated April 25, 2001
2235 ENTERPRISE STREET
SUITE 110
ESCONDIDO, CA 92029
    X    

Signatures

 /s/Steve Cooper   09/25/2019
**Signature of Reporting Person Date

 /s/Steve Cooper, Trustee   09/25/2019
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) 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.
(2) 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.
(3) Restricted stock units convert into common stock on a one-for-one basis.
(4) 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.

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