Edgar Filing: Murphy Michael R

Ownership Submission

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, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:

3235-0104

Expires:

January 31, 2005

Estimated average burden hours per response...

0.5

(Print or Type Responses)

1. Name and Address of Reporting Person ^*

Â Discovery Group I, LLC

2. Date of Event Requiring Statement (Month/Day/Year)
11/01/2010

3. Issuer Name and Ticker or Trading Symbol
AtriCure, Inc. [ATRC]

(Last)

(First)

(Middle)

191 N. WACKER DRIVE SUITE 1685,Â

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 Original Filed(Month/Day/Year)

(Street)

CHICAGO,Â ILÂ 60606

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 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	1,378,887 ⁽¹⁾	I	By Discovery Equity Partners, L.P. ⁽¹⁾
Common Stock	235,628 ⁽²⁾	I	By Pleiades Investment Partners - D, L.P ⁽²⁾

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
	Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

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 of Derivative Security: 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

Reporting Owners

Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
Discovery Group I, LLC 191 N. WACKER DRIVE SUITE 1685 CHICAGO,Â ILÂ 60606	Â	Â X	Â	Â
Murphy Michael R C/O DISCOVERY GROUP I, LLC 191 N. WACKER DRIVE SUITE 1685 CHICAGO,Â ILÂ 60606	Â	Â X	Â	Â
Donoghue Daniel J C/O DISCOVERY GROUP I, LLC 191 N. WACKER DRIVE SUITE 1685 CHICAGO,Â ILÂ 60606	Â	Â X	Â	Â

Signatures

Michael R. Murphy, Managing Director		11/02/2010
^**Signature of Reporting Person		Date
Daniel J. Donoghue		11/02/2010
^**Signature of Reporting Person		Date
Michael R. Murphy		11/02/2010
^**Signature of Reporting Person		Date

Explanation of Responses:

*	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).
(1)	Discovery Group I, LLC is the General Partner of Discovery Equity Partners, L.P., which is a discretionary client of the reporting person, that owns the reported securities. The reporting person disclaims beneficial ownership of the reported securities except to the extent of its pecuniary interest therein.
(2)	Discovery Group I, LLC is an investment manager for Pleiades Investment Partners - D, L.P., which is a discretionary client of the reporting person, that owns the reported securities. The reporting person disclaims beneficial ownership of the reported securities except to the extent of its pecuniary interest therein.
Â Remarks: MichaelÂ R.Â MurphyÂ andÂ DanielÂ J.Â DonoghueÂ areÂ managingÂ membersÂ ofÂ DiscoveryÂ GroupÂ I,Â LLC,Â andÂ eachÂ disclaimsÂ beneficialÂ ownershipÂ ofÂ theÂ reportedÂ securitiesÂ exceptÂ toÂ theÂ extentÂ ofÂ hisÂ pecuniaryÂ interestÂ therein.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, See Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.