Filing Details

The remainder of this cover page shall be filled out for a reporting persons initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

NAMES OF REPORTING PERSONS

NGP Energy Technology Partners II, L.P.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

(a)  ☐     (b)  ☐

SEC USE ONLY

CITIZENSHIP OR PLACE OF ORGANIZATION

State of Delaware

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH:

SOLE VOTING POWER

2,616,525

SHARED VOTING POWER

SOLE DISPOSITIVE POWER

2,616,525

SHARED DISPOSITIVE POWER

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

2,616,525 shares

CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

☐

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

13%(1)

TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

PN

This number represents the percentage obtained by: dividing (a) the total number of shares of the Issuers common stock being reported in this Statement (2,616,525) by (b) the number of shares of the Issuers common stock outstanding on October 31, 2019 (20,189,614).

NAMES OF REPORTING PERSONS

NGP ETP II, L.L.C.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

(a)  ☐     (b)  ☐

SEC USE ONLY

CITIZENSHIP OR PLACE OF ORGANIZATION

State of Delaware

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH:

SOLE VOTING POWER

2,616,525(1)

SHARED VOTING POWER

SOLE DISPOSITIVE POWER

2,616,525(1)

SHARED DISPOSITIVE POWER

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

2,616,525 shares

CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

☐

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

13%(2)

TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

CO

The reporting person is the general partner of NGP Energy Technology Partners II, L.P., which owns the reported securities. The reporting person disclaims beneficial ownership of the reported securities except to the extent of any pecuniary interest therein.

This number represents the percentage obtained by: dividing (a) the total number of shares of the Issuers common stock being reported in this Statement (2,616,525) by (b) the number of shares of the Issuers common stock outstanding on October 31, 2019 (20,189,614).

NAMES OF REPORTING PERSONS

Energy Technology Partners, L.L.C.

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

(a)  ☐     (b)  ☐

SEC USE ONLY

CITIZENSHIP OR PLACE OF ORGANIZATION

State of Delaware

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH:

SOLE VOTING POWER

2,616,525(1)

SHARED VOTING POWER

SOLE DISPOSITIVE POWER

2,616,525(1)

SHARED DISPOSITIVE POWER

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

2,616,525 shares

CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

☐

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

13%(2)

TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

CO

The reporting person is the sole manager of NGP ETP II, L.L.C., which is the general partner of NGP Energy Technology Partners II, L.P., which owns the reported securities. The reporting person disclaims beneficial ownership of the reported securities except to the extent of any pecuniary interest therein.

This number represents the percentage obtained by: dividing (a) the total number of shares of the Issuers common stock being reported in this Statement (2,616,525) by (b) the number of shares of the Issuers common stock outstanding on October 31, 2019 (20,189,614).

NAMES OF REPORTING PERSONS

Philip J. Deutch

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)

(a)  ☐     (b)  ☐

SEC USE ONLY

CITIZENSHIP OR PLACE OF ORGANIZATION

United States of America

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH:

SOLE VOTING POWER

2,616,525(1)

SHARED VOTING POWER

SOLE DISPOSITIVE POWER

2,616,525(1)

SHARED DISPOSITIVE POWER

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

2,616,525 shares

CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)

☐

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

13%(2)

TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)

IN

The reporting person is the sole member and manager of Energy Technology Partners, L.L.C., the manager of NGP ETP II, L.L.C. NGP ETP II, L.L.C. is the general partner of NGP Energy Technology Partners II, L.P., which owns the reported securities. The reporting person is also a member of the investment committee of NGP ETP II, L.L.C. By virtue of these relationships, the reporting person may be deemed to have the power to vote, or to direct the vote, and dispose of, or direct the disposition of, the reported securities held by NGP Energy Technology Partners II, L.P. The reporting person disclaims beneficial ownership of the reported securities except to the extent of any pecuniary interest therein.

This number represents the percentage obtained by: dividing (a) the total number of shares of the Issuers common stock being reported in this Statement (2,616,525) by (b) the number of shares of the Issuers common stock outstanding on October 31, 2019 (20,189,614).

Name of Issuer: GSE Systems, Inc.

Address of Issuers Principal Executive Offices: 1332 Londontown Blvd., Suite 200, Sykesville, MD 21784

Name of Person Filing: NGP Energy Technology Partners II, L.P. (NGP Energy Tech), NGP ETP II, L.L.C. (NGP GP), Energy Technology Partners, L.L.C. (ETP) and Philip J. Deutch (Deutch). NGP GP is the general partner of NGP Energy Tech. ETP is the sole manager of NGP GP and Deutch is the sole member and manager of ETP. Each of NGP Energy Tech, NGP GP, ETP and Deutch may be referred to herein as a Reporting Person

Address of Principal Business Office or, if none, Residence: The address and principal business office of each Reporting Person and is
1750 K Street NW, Suite 700, Washington, D.C. 20006.

Citizenship:

Title of Class of Securities: Common Stock, $.01 par value per share

CUSIP Number: 36227K106

Broker or dealer registered under Section 15 of the Act (15 U.S.C 78c).

Bank as defined in Section 3(a) (6) of the Act (15 U.S.C 78c).

Insurance Company as defined in Section 3(a) (19) of the Act (15 U.S.C 78c).

Investment Company registered under Section 8 of the Investment Company Act of 1940 (15 U.S.C 80a-8).

Investment Adviser in accordance with SS 240. 13d-1(b) (1) (ii) (E);

Employee Benefit Plan or Endowment Fund in accordance with SS 240. 13d-1(b) (ii) (F);

Parent Holding Company or Control Person in accordance with SS.SS.240. 13d-1(b) (ii) (G);

A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

A church plan that is excluded from the definition of an investment company under Section 3(c) (14) of the Investment Company Act of 1940(15 U.S.C 80a-3);

Group, in accordance with SS 240. 13d-1(b) (1) (ii) (J);

Amount beneficially owned:

Percent of class:

Number of shares as to which the person has:

Sole power to vote or to direct the vote

Shared power to vote or to direct the vote

Sole power to dispose or to direct the disposition of

Shared power to dispose or to direct the disposition of

NGP Energy Tech will have sole voting and dispositive power with respect to the shares of Common Stock of the Issuer beneficially owned by NGP Energy Tech. By virtue of the relationships between and among the Reporting Persons described in Item 2 of this Statement, NGP GP, ETP and Deutch may be deemed to have the power to direct the voting and disposition of the shares of Common Stock beneficially owned by NGP Energy Tech. NGP GP, ETP and Deutch disclaim beneficial ownership of the reported securities except to the extent of their pecuniary interests therein.