Amendment No. 2 to Investor's Rights Agreement

EXHIBIT 4.4

     THIS AMENDMENT NO. 2 TO INVESTOR’S RIGHTS AGREEMENT is entered into effective this 19th day of September, 2007 (this “Amendment No. 2”), by and among Cardiovascular Systems, Inc., a Minnesota Corporation (the “Company”) , the Series A-1 Convertible Preferred Stockholders listed on Exhibit A hereto (“Series A-1 Investors”), and the Investors signatory hereto.

RECITALS

     WHEREAS, this Amendment No. 2 amends an Investor’s Rights Agreement, dated July 19, 2006 (the "Investor’s Rights Agreement”) by and between the Company and the “Investors” set forth on Schedule A thereto and “Stockholders” set forth on Schedule B thereto, as amended by Amendment No. 1 to Investor’s Rights Agreement, dated October 3, 2006 by and between the Company, ITX International Equity Corp. and the “Investors” signatory thereto;

     WHEREAS, the Company has agreed to sell up to 2,941,177 shares of Series A-1 Convertible Preferred Stock to the Series A-1 Investors (the “Offering”) in accordance with the terms of that certain Private Placement Memorandum dated May 16, 2007, as supplemented on August 8, 2007, and those certain Subscription Agreements by and between the Company and the Series A-1 Investors received in connection with the Offering (the “Subscription Agreements”);

     WHEREAS, on May 21, 2007, the Company’s Board of Directors approved the sale of up to 1,175,000 shares of Series A-1 Convertible Preferred Stock to the Series A-1 Investors and the transactions contemplated by the Subscription Agreements including this Amendment No. 2, and on August 7, 2007 the Board further authorized that the Offering be increased to not more than 2,941,177 shares of Series A-1 Convertible Preferred Stock; and

     WHEREAS, Investors executing this Amendment No. 2 hold at least 66 2/3% of the combined voting power of the outstanding shares of Series A Preferred Stock and any Common Stock issued upon conversion of the Series A Preferred Stock.

     NOW THEREFORE, in consideration of the mutual covenants and agreements contained in this Amendment No. 2, the sufficiency of which is hereby acknowledged, the parties hereto agree as set forth below:

	1.		Defined Terms. Capitalized terms not defined herein shall have the meanings ascribed to them in the Investor’s Rights Agreement.
	2.		The Series A-1 Convertible Preferred Stock sold in the Offering shall be deemed additional shares of Series A Convertible Preferred Stock for purposes of the Investor’s Rights Agreement.

3.

Schedule A is hereby amended in its entirety as follows and each of the Series A-1 Investors shall be deemed an Investor as that term is used in the Investor’s Rights Agreement:

Investors

		Series A				Series A				Series A-1
		Preferred				Preferred				Preferred				Aggregate
Name of Investor		Shares				Warrant				Shares				Purchase Price
Easton Hunt Capital Partners, L.P.			612,960				87,040				—				—
Easton Hunt Partners, LP			612,960				87,040				—				—
Maverick Fund, L.D.C.			770,212				109,370				103,524			$	879,954.00
Maverick Fund USA, Ltd.			310,952				44,155				41,795			$	355,257.50
Maverick Fund II, Ltd.			670,149				95,161				90,075			$	765,637.50
Mitsui & Co. Venture Partners II, L.P.			675,148				95,871				117,647			$	999,999.50
ITX International Equity Corp.			350,263				49,737				47,079			$	400,171.50
Abrasive Technology, Inc. Profit Shar Pl			—				—				32,000			$	272,000.00
Michael Adrian			8,943				1,270				3,552			$	30,200.00
Mark R. Alvig			—				—				6,000			$	51,000.00
Shahla Amiri			—				—				5,000			$	42,500.00
Anthony Angelini			—				—				12,000			$	102,000.00
Michael J. Antonello			35,937				5,103				18,255			$	155,167.50
Massoud Arbabzadeh, MD			—				—				5,882			$	49,997.00
Naoum Baladi			—				—				28,000			$	238,000.00
Michael S. Barish			44,474				6,315				11,928			$	101,388.00
Frederick L. Betz and Cynthia A. Betz, JTWROS			—				—				6,000			$	51,000.00
RBC Dain Rauscher Cust FBO Frederick L. Betz IRA			—				—				9,500			$	80,750.00
Charles Schwab & Co. Cust FBO John A. Beyer IRA			—				—				5,882			$	50,000.00
Thomas M. Bies and Edith C. Bies, JTWROS			—				—				5,882			$	50,000.00
Gerry Black			—				—				5,882			$	50,000.00
Brent G. Blackey			—				—				5,900			$	50,150.00
Pensco Trust Company Cust FBO Michael J. Bogart IRA			—				—				4,900			$	41,650.00
William Bold			—				—				3,600			$	30,600.00
John R. Borrell			—				—				11,764			$	99,994.00
Robert Brady			—				—				9,000			$	76,500.00
Larry Brandt and Judy Brandt JTWROS			8,943				1,270				4,120			$	35,020.00
David Brink			10,260				1,457				17,000			$	144,500.00
Gerald F. Bubnick			—				—				2,942			$	25,007.00
Brian P. Burns, Jr.			—				—				7,500			$	63,750.00
Marlyn and Margaret Buss, Trustees, Marlyn and Margaret Buss Rev. Living Trust dated 4/12/04			—				—				5,882			$	50,000.00
Wedbush Morgan Securities Cust FBO Richard E. Bye IRA			—				—				7,050			$	59,925.00
Timothy Byrne and Sandra Byrne, Trustees, Byrne Family Trust			—				—				5,882			$	50,000.00
Christopher Campbell			—				—				2,941			$	25,000.00

		Series A				Series A				Series A-1
		Preferred				Preferred				Preferred				Aggregate
Name of Investor		Shares				Warrant				Shares				Purchase Price
H. Daniel Caparo			—				—				5,882			$	50,000.00
Charles Schwab & Co., Inc. Cust FBO Franklin G. Capitanini IRA			—				—				5,800			$	49,300.00
Joseph Anthony Cardenas			—				—				29,400			$	249,900.00
Curtis L. Carlson Family Foundation			43,783				6,217				29,414			$	250,019.00
Charles Schwab & Co., Inc. Cust FBO Steven W. Carter IRA			—				—				5,882			$	50,000.00
CAVA Partners, LLC			—				—				5,882			$	50,000.00
John F. Cavanaugh			—				—				3,000			$	25,500.00
Vijay T. Char			—				—				5,882			$	50,000.00
Scott Chase			—				—				17,647			$	150,000.00
Richard J. Cherry and JoAnn Cherry, JTWROS			—				—				2,942			$	25,007.00
George Jean Chilazi			—				—				6,777			$	57,604.50
Charles Schwab & Co., Inc. Cust FBO Bruce A. Church IRA			—				—				5,882			$	50,000.00
Pershing LLC Custodian FBO Walter Douglas Clark IRA			—				—				5,882			$	50,000.00
David E. Cohen, M.D.			—				—				5,884			$	50,014.00
Sean Collins			—				—				11,765			$	100,002.50
Wachovia Securities Cust FBO Sean Collins IRA			—				—				12,941			$	110,000.00
Tom Correia			—				—				5,882			$	50,000.00
Ralph D. Crawford			—				—				11,750			$	99,875.00
Carla C. Dahl			—				—				590			$	5,015.00
Thomas P. Davis, MD			—				—				5,882			$	50,000.00
Keith Donnan			—				—				5,882			$	50,000.00
Peter S. Dougan, M.D.			—				—				2,941			$	25,000.00
Charles Schwab & Co., Inc. Cust FBO Mark W. DuPont IRA			—				—				6,000			$	51,000.00
Keith M. Eastman			—				—				4,000			$	34,000.00
Joane Evans and Lyell Evans JTWROS			—				—				2,942			$	25,007.00
Ryan E. Evans			—				—				5,883			$	50,005.50
Gary Jay Fishbein, MD			—				—				6,000			$	51,000.00
Jeffrey Fleming			—				—				2,942			$	25,007.00
James Flynn			—				—				5,882			$	50,000.00
Linda M. Foster			17,890				2,540				2,404			$	20,434.00
Michael D. Fugit, M.D.			—				—				2,941			$	25,000.00
Michael Furlong			—				—				5,882			$	50,000.00
Geoffrey T. Gainor			—				—				5,882			$	50,000.00
Dennis R. Gancarz			—				—				5,882			$	50,000.00
GDN Holdings, LLC			131,349				18,652				41,913			$	356,260.50
Kenneth L. Gibbs, MD and Beverly T. Gibbs JTWROS			—				—				2,950			$	25,075.00
Scott Kean Goodman			—				—				19,059			$	162,001.50
UBS Financial Services, Inc. Cust FBO R. Hunt Greene IRA			—				—				6,500			$	55,250.00

		Series A				Series A				Series A-1
		Preferred				Preferred				Preferred				Aggregate
Name of Investor		Shares				Warrant				Shares				Purchase Price
Daniel Patrick Greenleaf and Diane Francis Greenleaf			—				—				10,000			$	85,000.00
Barry K. Griffith			—				—				18,750			$	159,375.00
Edith Guglielmi			—				—				7,060			$	60,010.00
David J. Gunther			—				—				2,941			$	25,000.00
Rob Hadley			—				—				2,941			$	25,000.00
Fiserv ISS & Co. Cust FBO Rob Hadley IRA			—				—				5,882			$	50,000.00
Scott Robert Hannum			—				—				11,764			$	100,000.00
Scott Merle Hanson			—				—				600			$	5,100.00
Steven J. Healy			8,815				1,252				9,431			$	80,173.50
Syntel, LLC Profit Sharing Plan FBO Alfred Harry Herget, Alfred Harry Herget, Trustee			—				—				5,882			$	49,997.00
Richard R. Heuser and Sharon L.Heuser, Trustees, R&S Trust dated 8/3/99			—				—				5,882			$	50,000.00
Charles Schwab & Co., Inc. Cust FBO David Richard Hewitt IRA			—				—				13,000			$	110,500.00
Robert C. Hinckle			—				—				17,647			$	150,000.00
William Hoffman and Lilia Helen Hoffman JTWROS			—				—				5,882			$	50,000.00
Jeremy Houseman			—				—				2,942			$	25,007.00
Derek J. Howe			—				—				8,000			$	68,000.00
Wende S. Hutton, Trustee, Hutton Living Trust dtd 12/10/96			—				—				5,882			$	50,000.00
Innovasc, LLC			—				—				4,500			$	38,250.00
Michael Iovanni and Linda Iovanni, JTWROS			—				—				2,941			$	25,000.00
Andrew J. Iseman and Shelly D. Iseman JTWROS			17,657				2,507				7,108			$	60,418.00
Sean Janzer			—				—				11,765			$	100,000.00
Sara Jay			—				—				5,900			$	50,150.00
Takemito Jimbo			—				—				11,765			$	100,002.50
Charles David Joffe, MD			—				—				6,000			$	51,000.00
Darla R. Johnson and John A. Beyer JTWROS			—				—				3,529			$	30,000.00
Elias H. Kassab			—				—				5,882			$	50,000.00
Salva Kassab and Suha Kassab JTWROS			—				—				3,529			$	30,000.00
KD Holding, Inc.			—				—				6,000			$	51,000.00
Puneet K. Khanna and Monica Khanna JTWROS			—				—				17,647			$	150,000.00
Yazan Khatib			—				—				2,941			$	25,000.00
Farhad Khosravi, Ttee, Farhad Khosravi and Flora Shirzad Khosravi Trust U/A			—				—				5,882			$	50,000.00
Bertram W. Klein			—				—				10,000			$	85,000.00
E*Trade as Cust FBO Joseph F. Koziol IRA			—				—				5,883			$	50,005.50

		Series A				Series A				Series A-1
		Preferred				Preferred				Preferred				Aggregate
Name of Investor		Shares				Warrant				Shares				Purchase Price
Al Kraus and Eileen Kraus JTWROS			—				—				8,825			$	75,012.50
Al Kraus			—				—				2,942			$	25,007.00
David Kraus, M.D.			—				—				3,000			$	25,500.00
Scott Kraus			—				—				22,600			$	192,100.00
John T. Kuzara			—				—				5,882			$	50,000.00
Habib John Lahlouh			—				—				6,000			$	51,000.00
David Lamadrid			—				—				2,942			$	25,007.00
Aaron Lew			—				—				17,000			$	144,500.00
MLPF&S Cust FBO Aaron Lew IRA			—				—				23,529			$	199,996.50
Robert Lindmeier and Sheryl Lindmeier			—				—				11,764			$	100,000.00
William Andrew Lindmeier and Susan J. Lindmeier JTWROS			—				—				5,000			$	42,500.00
Wells Fargo Bank, N.A. as Trustee of the Donald M. Longlet Rev Trust			—				—				11,764			$	99,994.00
Louis Lopez, MD			—				—				11,765			$	100,000.00
Richard A. Lotti			—				—				5,882			$	50,000.00
Jonathan K. Lubkert			—				—				600			$	5,100.00
Kenneth H. Lubkert and Elizabeth R. Lubkert JTWROS			—				—				4,706			$	40,001.00
Satyaprakash Makam			—				—				5,882			$	50,000.00
Louis Manfredo and Genevieve Manfredo JTWROS			—				—				2,942			$	25,007.00
Carol A. Martin, Sole Trustee of the Martin Family Revocable Trust			—				—				5,882			$	50,000.00
Lynne Martin and Tevis P. Martin III			—				—				1,200			$	10,200.00
MaxBee Holding Company LLC			—				—				5,882			$	50,000.00
Gary McCord			—				—				17,647			$	150,000.00
Christopher W. McNeill			—				—				5,882			$	50,000.00
John J. Mehalchin			—				—				11,765			$	100,002.50
Jacob P. Mercer			—				—				3,000			$	25,500.00
Amir Motarjeme, Trustee of the Amir Motarjeme Profit Sharing Plan FBO Amir Motarjeme			—				—				5,882			$	49,997.00
Padmini Natarajan and B. R. Natarajan JTWROS			—				—				5,882			$	50,000.00
Fiserv ISS & Co. Cust FBO Thomas P. Neslund IRA			—				—				5,882			$	50,000.00
Thomas P. Neslund			—				—				2,941			$	25,000.00
Hajime Oshita			—				—				2,400			$	20,400.00
Marco Ovikian and Catherine Ovikian, JTWROS			—				—				8,823			$	75,000.00
Ashish Pal			—				—				30,000			$	255,000.00
Tom Pardubeck			—				—				3,000			$	25,500.00
Daryl L. Peterman			1,027				146				5,000			$	42,500.00
Loyal M. Peterman, Jr.			20,564				2,920				16,124			$	137,054.00
John N. Phillips			—				—				5,882			$	50,000.00

		Series A				Series A				Series A-1
		Preferred				Preferred				Preferred				Aggregate
Name of Investor		Shares				Warrant				Shares				Purchase Price
Cassandra Piippo			—				—				589			$	5,006.50
Pinnacle Investment Group, LLC			—				—				9,000			$	76,500.00
Sridhar Prativadi			—				—				5,882			$	50,000.00
Rolando E. Prieto			—				—				2,941			$	24,998.50
Dave B. Radovich			7,203				1,023				25,169			$	213,936.50
Robert K. Ranum			—				—				2,941			$	24,998.50
Ambika Ravindran			—				—				12,000			$	102,000.00
Redmile Capital, LP			—				—				7,569			$	64,341.00
Redmile Ventures, LLC			—				—				5,882			$	49,997.00
Redmile Capital Offshore, Ltd.			—				—				27,725			$	235,658.00
Michael Reilly and Lisa Reilly			—				—				11,764			$	99,994.00
Ronald Reuss and Rita Reuss JTWROS			—				—				3,000			$	25,500.00
Stacey Rickert			—				—				10,000			$	85,000.00
Benjamin S. Rinkey			—				—				4,000			$	34,000.00
Caleb Rivera			—				—				2,940			$	24,990.00
Edward Todd Robbins			—				—				2,941			$	25,000.00
Cecilia S. Roberts, Trustee David K. Roberts Residuary Trust			—				—				21,200			$	180,200.00
David K. Roberts			—				—				11,800			$	100,300.00
Todd A. Roberts and Debra D. Roberts			—				—				5,882			$	50,000.00
Peter Lars Runquist			—				—				5,882			$	50,000.00
Paul W. Schaffer			10,216				1,451				20,000			$	170,000.00
James W. Schlesing and Dona Connelly			—				—				7,059			$	60,001.50
Marc S. Schwartzberg			—				—				2,941			$	25,000.00
Gary M. Scott and Malisa M. Scott, Ttees of the Gary and Malisa Scott Rev Trust			—				—				29,500			$	250,750.00
R. Randolph Scott			—				—				5,882			$	50,000.00
Gino J. Sedillo, MD			—				—				5,882			$	50,000.00
David Shaskey			—				—				5,882			$	50,000.00
Pamela Shaw and James Shaw JTWROS			—				—				5,882			$	50,000.00
Neil J. Sheehan			—				—				2,000			$	17,000.00
Chiemsee Money Purchase Plan, dtd 03/11/97, FBO Robert T. Shepard			—				—				6,000			$	51,000.00
Robert Shepard and Celia Shepard, Ttees of the Shepard Family Trust dated 2/1/99			—				—				6,000			$	51,000.00
Harvinder Paul Singh, MD			—				—				5,882			$	50,000.00
Kevin Spanier			—				—				1,200			$	10,200.00
Kathleen A. Stauter			—				—				1,775			$	15,087.50
Steven Mendelow, Trustee, Teledata Financial Services Corp. Profit Shar Plan			—				—				23,529			$	200,000.00
Charles Schwab & Co., Inc. Cust FBO Robert J. Thatcher IRA			—				—				12,000			$	102,000.00
Kimberley J. Thomas and A. Conrade Thomas JTWROS			—				—				5,890			$	50,065.00

		Series A				Series A				Series A-1
		Preferred				Preferred				Preferred				Aggregate
Name of Investor		Shares				Warrant				Shares				Purchase Price
TMP, LLLP			53,217				7,557				56,768			$	482,529.00
Top Medical Holding B.V.			—				—				4,000			$	34,000.00
Leslie Trigg and Michael Trigg, Trustees, Trigg Family Trust			—				—				2,942			$	25,007.00
Edwin C. Tyska			—				—				11,765			$	100,000.00
Hector J. Vasquez and Sandra L. Vasquez			—				—				3,000			$	25,500.00
Greg Vella and Michelle Vella, Ttees, Greg Vella and Michelle Vella Family Tr			—				—				5,882			$	50,000.00
Chris Vieira			—				—				4,588			$	39,000.00
Douglas A. Waldo, MD			—				—				3,000			$	25,500.00
Joseph A. Wasselle and Stacie Poole			—				—				2,941			$	24,998.50
Charles Schwab & Co., Inc. Cust FBO Burton M. Waxman IRA			—				—				7,058			$	60,000.00
Wellspring Capital			—				—				176,470			$	1,500,000.00
Wellspring Management, LLC			—				—				58,823			$	500,000.00
Martin F. Whalen			—				—				5,882			$	50,000.00
Fiserv ISS & Co. Cust FBO Kimberly Williamson IRA			—				—				5,882			$	50,000.00
Steven Wishnia			—				—				3,000			$	25,500.00
Sharon T. Wooster			—				—				2,941			$	25,000.00
Total			4,002,644				568,374				2,188,425			$	18,601,821.50

	4.		This Amendment No. 2 may be executed in any number of original or facsimile counterparts, and each such counterpart hereof shall be deemed to be an original instrument, but all such counterparts together shall constitute but one agreement. Any counterpart or other signature to this Amendment No. 2 that is delivered by facsimile shall be deemed for all purposes as constituting good and valid execution and delivery by such party of this Amendment No. 2.
	5.		Except as set forth herein, all other terms and conditions of the Investor’s Rights Agreement remain the same.

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

     IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Investor’s Rights Agreement effective the date first written above.

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Investor’s Rights Agreement effective the date first written above.

		EASTON HUNT CAPITAL PARTNERS, L.P.
		By:		EHC GP, L.P. its General Partner
		By:		EHC GP, Inc., its General Partner
		By:		/s/ John H. Friedman
				Name: John H. Friedman Title: President
		EASTON CAPITAL PARTNERS, LP
		By:		ECP GP, LLC
		By:		ECP GP, Inc., its Manager
		By:		/s/ John H. Friedman
				Name: John H. Friedman
				Title: President

     IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Investor’s Rights Agreement effective the date first written above.

		MAVERICK FUND, L.D.C.
		By:		Maverick Capital, Ltd.
				Its Investment Advisor
		By:		/s/ John T. McCafferty
				Name: John T. McCafferty
				Title: Limited Partner and General Counsel
		MAVERICK FUND USA, LTD.
		By:		Maverick Capital, Ltd.
				Its Investment Advisor
		By:		/s/ John T. McCafferty
				Name: John T. McCafferty
				Title: Limited Partner and General Counsel
		MAVERICK FUND II, LTD.
		By:		Maverick Capital, Ltd.
				Its Investment Advisor
		By:		/s/ John T. McCafferty
				Name: John T. McCafferty
				Title: Limited Partner and General Counsel

     IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Investor’s Rights Agreement effective the date first written above.

		MITSUI & CO. VENTURE PARTNERS II, L.P.
		By:		Mitsui & Co. Venture Partners, Inc.
				Its General Partner
		By:		/s/ Koichi Ando
				Name: Koichi Ando
				Title: President & CEO

     IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Investor’s Rights Agreement effective the date first written above.

EXHIBIT A

SERIES A-1 CONVERTIBLE PREFERRED INVESTORS

Abrasive Technology, Inc. Profit Sharing Plan

Michael Adrian

Mark R. Alvig

Shahla Amiri

Anthony Angelini

Michael J. Antonello

Massoud Arbabzadeh, MD

Naoum Baladi

Michael S. Barish

Frederick L. Betz and Cynthia A. Betz, JTWROS

RBC Dain Rauscher Cust FBO Frederick L. Betz IRA

Charles Schwab & Co. Cust FBO John A. Beyer IRA

Thomas M. Bies and Edith C. Bies, JTWROS

Gerry Black

Brent G. Blackey

Pensco Trust Company Cust FBO Michael J. Bogart IRA

William Bold

John R. Borrell

Robert Brady

Larry Brandt and Judy Brandt JTWROS

David Brink

Gerald F. Bubnick

Brian P. Burns, Jr.

Marlyn and Margaret Buss, Ttees, Marlyn and Margaret Buss Rev. Living Trust

Wedbush Morgan Securities Cust FBO Richard E. Bye IRA

Timothy Byrne and Sandra Byrne, Trustees,

Byrne Family Trust

Christopher Campbell

H. Daniel Caparo

Charles Schwab & Co., Inc. Cust FBO Franklin G. Capitanini IRA

Joseph Anthony Cardenas

Curtis L. Carlson Family Foundation

Charles Schwab & Co., Inc. Cust FBO Steven W. Carter IRA

CAVA Partners, LLC

John F. Cavanaugh

Vijay T. Char

Scott Chase

Richard J. Cherry and JoAnn Cherry, JTWROS

George Jean Chilazi

Charles Schwab & Co., Inc. Cust FBO Bruce A. Church IRA

Pershing LLC Custodian FBO Walter Douglas Clark IRA

David E. Cohen, M.D.

Sean Collins

Wachovia Securities Cust FBO Sean Collins IRA

Tom Correia

Ralph D. Crawford

Carla C. Dahl

Thomas P. Davis, MD

Keith Donnan

Peter S. Dougan, M.D.

Charles Schwab & Co., Inc. Cust FBO Mark W. DuPont IRA

Keith M. Eastman

Joane Evans and Lyell Evans JTWROS

Ryan E. Evans

Gary Jay Fishbein, MD

Jeffrey Fleming

James Flynn

Linda M. Foster

Michael D. Fugit, M.D.

Michael Furlong

Geoffrey T. Gainor

Dennis R. Gancarz

GDN Holdings, LLC

Kenneth L. Gibbs, MD and Beverly T. Gibbs JTWROS

Scott Kean Goodman

UBS Financial Services, Inc. Cust FBO R. Hunt Greene IRA

Daniel Patrick Greenleaf and Diane Francis Greenleaf

Barry K. Griffith

Edith Guglielmi

David J. Gunther

Rob Hadley

Fiserv ISS & Co. Cust FBO Rob Hadley IRA

Scott Robert Hannum

Scott Merle Hanson

Steven J. Healy

Syntel, LLC Profit Sharing Plan FBO Alfred Harry Herget, Alfred Harry Herget, Trustee

Richard R. Heuser and Sharon L. Heuser, Trustees, R&S Trust dated 8/3/99

Charles Schwab & Co., Inc. Cust FBO David Richard Hewitt IRA

Robert C. Hinckle

William Hoffman and Lilia Helen Hoffman JTWROS

Jeremy Houseman

Derek J. Howe

Wende S. Hutton, Trustee, Hutton Living Trust dtd 12/10/96

Innovasc, LLC

Michael Iovanni and Linda Iovanni, JTWROS

Andrew J. Iseman and Shelly D. Iseman JTWROS

ITX International Equity Corp.

Sean Janzer

Sara Jay

Takemito Jimbo

Charles David Joffe, MD

Darla R. Johnson and John A. Beyer JTWROS

Elias H. Kassab

Salva Kassab and Suha Kassab JTWROS

KD Holding, Inc.

Puneet K. Khanna and Monica Khanna JTWROS

Yazan Khatib

Farhad Khosravi, Ttee, Farhad Khosravi and Flora Shirzad Khosravi Trust U/A

Bertram W. Klein

E*Trade as Cust FBO Joseph F. Koziol IRA

Al Kraus and Eileen Kraus JTWROS

Al Kraus

David Kraus, M.D.

Scott Kraus

John T. Kuzara

Habib John Lahlouh

David Lamadrid

Aaron Lew

MLPF&S Cust FBO Aaron Lew IRA

Robert Lindmeier and Sheryl Lindmeier

William Andrew Lindmeier and Susan J. Lindmeier JTWROS

Wells Fargo Bank, N.A. as Trustee of the Donald M. Longlet Rev Tr

Louis Lopez, MD

Richard A. Lotti

Jonathan K. Lubkert

Kenneth H. Lubkert and Elizabeth R. Lubkert JTWROS

Satyaprakash Makam

Louis Manfredo and Genevieve Manfredo JTWROS

Carol A. Martin, Sole Trustee, Martin Family Revocable Trust

Lynne Martin and Tevis P. Martin III

Maverick Fund, L.D.C.

Maverick Fund USA, Ltd.

Maverick Fund II, Ltd.

MaxBee Holding Company LLC

Gary McCord

Christopher W. McNeill

John J. Mehalchin

Jacob P. Mercer

Mitsui & Co. Venture Partners II, LP

Amir Motarjeme, Trustee, Amir Motarjeme Profit Sharing Plan FBO Amir Motarjeme

Padmini Natarajan and B. R. Natarajan JTWROS

Fiserv ISS & Co. Cust FBO Thomas P. Neslund IRA

Thomas P. Neslund

Hajime Oshita

Marco Ovikian and Catherine Ovikian, JTWROS

Ashish Pal

Tom Pardubeck

Daryl L. Peterman

Loyal M. Peterman, Jr.

John N. Phillips

Cassandra Piippo

Pinnacle Investment Group, LLC

Sridhar Prativadi

Rolando E. Prieto

Dave B. Radovich

Robert K. Ranum

Ambika Ravindran

Redmile Capital, LP

Redmile Ventures, LLC

Redmile Capital Offshore, Ltd.

Michael Reilly and Lisa Reilly

Ronald Reuss and Rita Reuss JTWROS

Stacey Rickert

Benjamin S. Rinkey

Caleb Rivera

Edward Todd Robbins

Cecilia S. Roberts, Trustee David K. Roberts Residuary Trust

David K. Roberts

Todd A. Roberts and Debra D. Roberts

Peter Lars Runquist

Paul W. Schaffer

James W. Schlesing and Dona Connelly

Marc S. Schwartzberg

Gary M. Scott and Malisa M. Scott, Ttees of the Gary and Malisa Scott Rev Trust

R. Randolph Scott

Gino J. Sedillo, MD

David Shaskey

Pamela Shaw and James Shaw JTWROS

Neil J. Sheehan

Chiemsee Money Purchase Plan, dtd 03/11/97, FBO Robert T. Shepard

Robert Shepard and Celia Shepard, Ttees of the Shepard Family Trust dated 2/1/99

Harvinder Paul Singh, MD

Kevin Spanier

Kathleen A. Stauter

Steven Mendelow, Trustee, Teledata Financial Services Corp. Profit Shar Plan

Charles Schwab & Co., Inc. Cust FBO Robert J. Thatcher IRA

Kimberley J. Thomas and A. Conrade Thomas JTWROS

TMP, LLLP

Top Medical Holding B.V.

Leslie Trigg and Michael Trigg, Trustees, Trigg Family Trust

Edwin C. Tyska

Hector J. Vasquez and Sandra L. Vasquez

Greg Vella and Michelle Vella, Ttees, Greg Vella and Michelle Vella Family Tr

Chris Vieira

Douglas A. Waldo, MD

Joseph A. Wasselle and Stacie Poole

Charles Schwab & Co., Inc. Cust FBO Burton M. Waxman IRA

Wellspring Capital

Wellspring Management, LLC

Martin F. Whalen

Fiserv ISS & Co. Cust FBO Kimberly Williamson IRA

Steven Wishnia

Sharon T. Wooster