Sec Form 4 Filing - Explorer Parent LLC @ GRID DYNAMICS HOLDINGS, INC. - 2020-06-09

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 Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person Explorer Parent LLC 2. Issuer Name and Ticker or Trading Symbol GRID DYNAMICS HOLDINGS, INC. [ GDYN] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director X __ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) 533 AIRPORT BOULEVARD, SUITE 400 3. Date of Earliest Transaction (MM/DD/YY) 06/09/2020 (Street) BURLINGAME, CA94010 4. If Amendment, Date Original Filed (MM/DD/YY) 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 (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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 06/09/2020 S 6,454 D $ 9.0024 ( 1 ) 46,546 I See footnote ( 2 ) ( 3 ) Common Stock 06/10/2020 S 46,546 D $ 8.876 ( 4 ) 0 I See footnote ( 2 ) ( 3 ) Common Stock 6,030,000 I See footnote ( 3 ) ( 5 )

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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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 (MM/DD/YY) 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

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Explorer Parent LLC 533 AIRPORT BOULEVARD SUITE 400 BURLINGAME, CA94010 X Founder Holdings LLC 533 AIRPORT BOULEVARD SUITE 400 BURLINGAME, CA94010 X Chaserg Technology Sponsor LLC 533 AIRPORT BOULEVARD SUITE 400 BURLINGAME, CA94010 X Signatures Explorer Parent LLC By: Founder Holdings LLC, its managing member, By: /s/ Steven Fletcher, a Managing Member, By: /s/ Alex Vieux, a Managing Member 06/12/2020 Signature of Reporting Person Date Founder Holdings LLC By: /s/ Steven Fletcher, a Managing Member, By: /s/ Alex Vieux, a Managing Member 06/12/2020 Signature of Reporting Person Date ChaSerg Technology Sponsor LLC By: /s/ Steven Fletcher, a Managing Member 06/12/2020 Signature of Reporting Person Date

Explanation of Responses:

( 1 )The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $9.00 to $9.06. The reporting person undertakes to provide Grid Dynamics Holdings, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. ( 2 )Explorer Parent LLC ("Explorer") is the record holder of the securities reported herein. Founder Holdings LLC ("Founder"), as the managing member of Explorer, may be deemed to share beneficial ownership of these securities. ( 3 )By virtue of the relationships between Explorer, Founder and ChaSerg Technology Sponsor LLC ("Sponsor"), each of Explorer and Founder may be deemed to share beneficial ownership of the securities held of record by Sponsor. ( 4 )The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $8.75 to $9.035. The reporting person undertakes to provide the Company, any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. ( 5 )By Sponsor.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* 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).

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