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* PRESIDIO MANAGEMENT GROUP VIII L L C (Last) (First) (Middle) 2735 SAND HILL ROAD (Street) MENLO PARK CA 94025 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 08/05/2005	3. Issuer Name and Ticker or Trading Symbol AtriCure, Inc. [ ATRC ]
		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)

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
Series A Preferred Stock	(1)	(1)	Common Stock	1,022,035	$0(1)	I	Directly held by USVP VIII(2)
Series A Preferred Stock	(1)	(1)	Common Stock	7,531	$0(1)	I	Directly held by AFF VIII(2)
Series A Preferred Stock	(1)	(1)	Common Stock	9,575	$0(1)	I	Directly held by EP VIII-A(2)
Series A Preferred Stock	(1)	(1)	Common Stock	5,137	$0(1)	I	Directly held by EP VIII-B(2)
Series B Preferred Stock	(1)	(1)	Common Stock	1,440,854	$0(1)	I	Directly held by USVP VIII(2)
Series B Preferred Stock	(1)	(1)	Common Stock	10,617	$0(1)	I	Directly held by AFF VIII(2)
Series B Preferred Stock	(1)	(1)	Common Stock	13,498	$0(1)	I	Directly held by EP VIII-A(2)
Series B Preferred Stock	(1)	(1)	Common Stock	7,242	$0(1)	I	Directly held by EP VIII-B(2)
Warrant	08/05/2005	08/05/2006	Common Stock	92,773	$5.43	I	Directly held by USVP VIII(2)
Warrant	08/05/2005	08/05/2006	Common Stock	683	$5.43	I	Directly held by AFF VIII(2)
Warrant	08/05/2005	08/05/2006	Common Stock	869	$5.43	I	Directly held by EP VIII-A(2)
Warrant	08/05/2005	08/05/2006	Common Stock	466	$5.43	I	Directly held by EP VIII-B(2)

1. Name and Address of Reporting Person* PRESIDIO MANAGEMENT GROUP VIII L L C (Last) (First) (Middle) 2735 SAND HILL ROAD (Street) MENLO PARK CA 94025 (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* PHILLIPS STUART G (Last) (First) (Middle) 2735 SAND HILL ROAD (Street) MENLO PARK CA 94025 (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* ROOT JONATHAN D (Last) (First) (Middle) 2735 SAND HILL ROAD (Street) MENLO PARK CA 94025 (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* Rust Christopher J (Last) (First) (Middle) 2735 SAND HILL ROAD (Street) MENLO PARK CA 94025 (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* YOUNG PHILIP M (Last) (First) (Middle) 2735 SAND HILL ROAD (Street) MENLO PARK CA 94025 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. The shares of Preferred Stock shall convert on a 1-for-1 basis into Common Stock upon the closing of the Issuer's initial public offering.

2. See additional Form 4 filed by Presidio Management Group VIII, LLC ("PMG VIII") for additional members of this joint filing. PMG VIII is the general partner of US Venture Partners VIII, L.P. ("USVP VIII"), USVP Entrepreneur Partners VIII-A, L.P. ("EP VIII-A"), USVP Entrepreneur Partners VIII-B, L.P. ("EP VIII-B"), and USVP VIII Affiliates Fund, L.P. ("AFF VIII"), and Timmothy Connors, Irwin Federman, Winston S. Fu, Steven M. Krausz, David E. Liddle, Stuart G. Phillips, Jonathan D. Root, Christopher Rust, and Philip M. Young, the managing members of PMG VIII, may be deemed to share voting and dispositive power over the shares held by USVP VIII, EP VIII-A, EP VIII-B and AFF VIII. Such persons and entities disclaim beneficial ownership of shares held by USVP VIII, EP VIII-A, EP VIII-B and AFF VIII except to the extent of any pecuniary interest therein.

Remarks:

	Michael P. Maher - Attorney in fact for each joint filer	08/08/2005
	** Signature of Reporting Person	Date
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