SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF 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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1. Name and Address of Reporting Person* Barney Charles L (Last) (First) (Middle) 952 ECHO LANE, SUITE 364 (Street) HOUSTON TX 77024 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 08/04/2004	3. Issuer Name and Ticker or Trading Symbol NATURAL GAS SERVICES GROUP INC [ NGS ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)	5. If Amendment, Date of 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

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	549,574	I	By CBarney Investments, Ltd.
Common Stock	105,000	I	By Mark X Energy Company

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Warrants	10/21/2002	10/20/2006	Common Stock	47,000	$6.25	I	By CBarney Investments, Ltd.
Warrants	10/21/2002	10/20/2006	Common Stock	168,500	$6.25	I	By Mark X Energy Company

1. Name and Address of Reporting Person* Barney Charles L (Last) (First) (Middle) 952 ECHO LANE, SUITE 364 (Street) HOUSTON TX 77024 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Mark X Energy CO (Last) (First) (Middle) 952 ECHO LANE, SUITE 364 (Street) HOUSTON TX 77024 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) 10% Owner as Member of Group

1. Name and Address of Reporting Person* CBarney Investments, Ltd. (Last) (First) (Middle) 952 ECHO LANE, SUITE 364 (Street) HOUSTON TX 77024 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director 10% Owner Officer (give title below) X Other (specify below) 10% Owner as Member of Group

Explanation of Responses:

	Telisa Webb Schelin as attorney-in-fact for Charles L. Barney	08/13/2004
	Telisa Webb Schelin as attorney-in-fact for Mark X Energy Company	08/13/2004
	Telisa Webb Schelin as attorney-in-fact for CBarney Investments, Ltd.	08/13/2004
	** Signature of Reporting Person	Date
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 5 (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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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