Douglas Braunstein’s Hudson Executive Capital Selling Atricure Inc. (ATRC)

1	NAMES OF REPORTING PERSON    Hudson Executive Capital LP
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)  ☐  (b)  ☐
3	SEC USE ONLY
4	SOURCE OF FUNDS AF
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)			☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION    Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 0
		8	SHARED VOTING POWER 1,882,494
		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 1,882,494
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 1,882,494
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES			☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES 4.98%(1)
14	TYPE OF REPORTING PERSON PN, IA

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(1)

The percentage calculations herein are based upon an aggregate of 37,812,869 shares of common stock, par value $.001 per share, of AtriCure, Inc. outstanding as of the completion of AtriCure, Inc.’s offering of common stock on or about October 10, 2018, as reported in AtriCure, Inc.’s prospectus supplement filed pursuant to Rule 424(b)(5) on October 5, 2018.

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(2)

The percentage calculations herein are based upon an aggregate of 37,812,869 shares of common stock, par value $.001 per share, of AtriCure, Inc. outstanding as of the completion of AtriCure, Inc.’s offering of common stock on or about October 10, 2018, as reported in AtriCure, Inc.’s prospectus supplement filed pursuant to Rule 424(b)(5) on October 5, 2018.

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(3)

The percentage calculations herein are based upon an aggregate of 37,812,869 shares of common stock, par value $.001 per share, of AtriCure, Inc. outstanding as of the completion of AtriCure, Inc.’s offering of common stock on or about October 10, 2018, as reported in AtriCure, Inc.’s prospectus supplement filed pursuant to Rule 424(b)(5) on October 5, 2018.

This amendment No. 2 (“Amendment No. 2”) to Schedule 13D relates to the Schedule 13D filed on January 24, 2017 (the “Original Schedule 13D”, as amended and supplemented through the date of this Amendment No. 2, the “Schedule 13D”) by (i) Hudson Executive Capital LP, a Delaware limited partnership (“Hudson Executive”); (ii) HEC Management GP LLC, a Delaware limited liability company (“Management GP”); and (iii) Douglas L. Braunstein, a citizen of the United States of America (together with Hudson Executive and Management GP, the “Reporting Persons”) relating to the common stock, par value $.001 per share (the “Shares”), of AtriCure, Inc., a Delaware corporation (the “Issuer”).

Capitalized terms used but not defined in this Amendment No. 2 shall have the meaning set forth in the Schedule 13D.

Except as specifically amended by this Amendment No. 2, the Schedule 13D is unchanged.

ITEM 1. SECURITY AND ISSUER

The second paragraph of Item 1 of this Schedule 13D is amended and restated in its entirety as follows:

“The Reporting Persons (as defined below) beneficially own an aggregate of 1,882,494 Shares (the “Subject Shares”). The Subject Shares represent approximately 4.98% of the issued and outstanding Shares based on 37,812,869 Shares outstanding as of the completion of the Issuer’s offering of common stock on or about October 10, 2018, as reported in the Issuer’s prospectus supplement filed pursuant to Rule 424(b)(5) on October 5, 2018.”

ITEM 2. IDENTITY AND BACKGROUND

Item 2(b) of this Schedule 13D is amended and restated in its entirety as follows:

ITEM 3. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION

Item 3 of this Schedule 13D is amended and restated in its entirety as follows:

“As of the date hereof, the Reporting Persons are deemed to beneficially own the Subject Shares as detailed in Items 1 and 5. The aggregate purchase price for the 1,882,494 Subject Shares is $29,849,123.70.

The source of funding for the transactions pursuant to which the Reporting Persons obtained beneficial ownership of the Shares was derived from the respective capital of the HEC Funds.”

ITEM 4. PURPOSE OF TRANSACTION

Item 4 of this Schedule 13D is amended and supplemented by adding the following information as the final paragraph of Item 4:

“The Issuer filed a prospectus supplement pursuant to Rule 424(b)(5) on October 5, 2018 reporting on a common stock offering of 2,500,000 Shares expected to close on or about October 10, 2018. As a result of this offering and the sale by the Reporting Persons, on behalf of Hudson Executive, of certain Shares for portfolio management purposes, the beneficial ownership of the Reporting Persons fell to below 5% of the outstanding Shares of the Issuer. The trades are set forth in Exhibit 4.”

ITEM 5. INTEREST IN SECURITIES OF THE ISSUER

Item 5(c) of this Schedule 13D is amended and restated in its entirety as follows:

Item 5(e) of this Schedule 13D is amended and restated in its entirety as follows:

ITEM 7. MATERIAL TO BE FILED AS EXHIBITS

Item 7 of the Schedule 13D is hereby amended and supplemented by adding a reference to the following exhibit:

SIGNATURE

After reasonable inquiry and to the best of each of the undersigned’s knowledge and belief, each of the undersigned certify that the information set forth in this statement is true, complete and correct.

Date: October 9, 2018

	HUDSON EXECUTIVE CAPITAL LP By: HEC Management GP LLC, its general partner
	By:	/s/ Douglas L. Braunstein
		Name: Douglas L. Braunstein
		Title: Managing Member

	HEC MANAGEMENT GP LLC
	By:	/s/ Douglas L. Braunstein
		Name: Douglas L. Braunstein
		Title: Managing Member

	DOUGLAS L. BRAUNSTEIN
	By:	/s/ Douglas L. Braunstein
		Douglas L. Braunstein

INDEX TO EXHIBITS

*Previously Filed