NxStage Medical: Committee Composition

	Audit	Nominating and Governance	Compensation
Philippe Chambon, M.D., Ph.D.
Chairman Philippe O. Chambon, M.D., Ph.D., age 53, has served as a director of NxStage since 1998, has been Chairman of our Board of Directors since December 2004 and currently serves on our Compensation and Nominating and Corporate Governance Committees. Dr. Chambon is a Managing Director and founder of New Leaf Venture Partners, a spin-off from The Sprout Group, or Sprout. He joined Sprout in May 1995 and became a General Partner in January 1997. He invests broadly in healthcare technology companies. He also is currently on the board of ePocrates, Inc. as well as several private companies. From May 1993 to April 1995 Dr. Chambon was a Manager in the Healthcare Practice of The Boston Consulting Group. From September 1987 to April 1993, he was an executive with Sandoz Pharmaceutical, where he led strategic product development, portfolio management and pre-marketing activities in his capacity as Executive Director of New Product Management. Dr. Chambon did graduate research in molecular immunology at The Pasteur Institute and earned a MD, Ph.D. from the University of Paris. He also has an MBA from Columbia University in New York. Dr. Chambon brings leadership, corporate governance, strategic, capital market and small company build-up experience, within the healthcare technology sector, to our Board. Holdings: 1,298,151 shares     View Transactions Date Type Shares Traded Price Range 01/09/2012 Disposition (Non Open Market) 863,676 17.86 12/30/2011 Acquisition (Non Open Market) 773 n/a 09/30/2011 Acquisition (Non Open Market) 491 n/a 09/14/2011 Sell 20,110 18.58 09/08/2011 Sell 53,102 18.42 09/01/2011 Sell 36,977 17.79 - 18.52 09/01/2011 Option Execute 112,862 5.50 08/31/2011 Sell 57,480 18.47 08/16/2011 Disposition (Non Open Market) 1,092,830 18.46 06/30/2011 Acquisition (Non Open Market) 756 n/a 05/26/2011 Disposition (Non Open Market) 8,174 18.55 05/26/2011 Option Execute 14,000 10.83 03/31/2011 Acquisition (Non Open Market) 466 n/a 01/26/2011 Disposition (Non Open Market) 803,916 24.39 12/31/2010 Acquisition (Non Open Market) 472 n/a 12/09/2010 Sell 300 22.51 12/08/2010 Sell 26,749 22.59 12/07/2010 Sell 168,975 23.20 12/06/2010 Option Execute 4,170 5.50 11/08/2010 Disposition (Non Open Market) 1,200,000 21.30 09/30/2010 Acquisition (Non Open Market) 641 n/a 09/14/2010 Option Execute 12,000 12.59 08/16/2010 Sell 100,000 17.01 08/11/2010 Sell 500,000 16.00 08/09/2010 Sell 44,700 16.19 08/06/2010 Sell 33,400 16.03 08/05/2010 Sell 37,100 16.36 08/04/2010 Sell 100,000 16.33 08/03/2010 Sell 300,000 16.32 07/30/2010 Sell 28,800 16.09 07/29/2010 Sell 48,800 16.07 07/28/2010 Sell 130,200 16.90 07/27/2010 Sell 204,473 16.97 06/30/2010 Acquisition (Non Open Market) 1,061 n/a 03/31/2010 Acquisition (Non Open Market) 895 n/a 12/31/2009 Acquisition (Non Open Market) 1,287 n/a
Daniel A. Giannini, C.P.A.
Daniel A. Giannini, age 61, has served as a director of NxStage since October 2005 and currently serves as chair of our Audit Committee and a member of our Nominating and Corporate Governance Committee. He also serves as a director on several private and non-profit company boards. Mr. Giannini retired in June 2005, after a more than 30-year career as a Certified Public Accountant with PricewaterhouseCoopers LLP. During his last five years at PricewaterhouseCoopers LLP, Mr. Giannini served as an audit partner and led the firm's Atlanta office's Technology, Information, Communications and Entertainment practice. Mr. Giannini received a B.S. degree in Business Administration from LaSalle University. Mr. Giannini brings corporate governance, internal control and financial reporting experience to the Board. Holdings: 40,296 shares     View Transactions Date Type Shares Traded Price Range 12/30/2011 Acquisition (Non Open Market) 576 n/a 09/30/2011 Acquisition (Non Open Market) 563 n/a 06/30/2011 Acquisition (Non Open Market) 780 n/a 03/31/2011 Acquisition (Non Open Market) 534 n/a 03/11/2011 Disposition (Non Open Market) 7,407 20.47 03/11/2011 Option Execute 14,000 10.83 12/31/2010 Acquisition (Non Open Market) 130 n/a 09/30/2010 Acquisition (Non Open Market) 772 n/a 08/13/2010 Disposition (Non Open Market) 11,687 16.16 08/13/2010 Option Execute 15,000 12.59 06/30/2010 Acquisition (Non Open Market) 1,297 n/a 03/31/2010 Acquisition (Non Open Market) 1,113 n/a 12/31/2009 Acquisition (Non Open Market) 1,107 n/a
Nancy J. Ham
Nancy J. Ham, age 49, has served as a director of NxStage since January 2011. Since July 2008, Ms. Ham has been the President, CEO and director of MedVentive, Inc., a leading provider of physician performance management solutions for healthcare delivery networks and payers. From 2005 to 2007 she served as President of Sentillion, Inc. Before joining Sentillion, Ms. Ham served in various executive capacities at ProxyMed, Inc., including President and COO, and Healtheon/WebMD Corporation. Ms. Ham holds a BA in economics from Duke University and a Masters in International Business Studies (MIBS) from the University of South Carolina. Ms Ham brings in-depth healthcare IT industry experience and adds to the Board's diversity.
Earl R. Lewis
Earl R. Lewis, age 67, has served as a director of NxStage since October 2008 and currently serves as a member of our Compensation Committee. Since 2000, Mr. Lewis has been the Chairman, President and CEO of Flir Systems Inc., a manufacturer of thermal imaging and infrared camera systems. Prior to 2000, he served as CEO and President at Thermo Instrument Systems, Inc. He also served Thermo in various executive capacities, including President and Chief Operating Officer, CEO and President of Thermo Optek Corp., and President of Thermo Jarrell Ash Corp. In addition to serving on the board of Flir Systems, Inc., Mr. Lewis is a member of the Board of Directors of Harvard BioScience and American DG Energy, Inc. Mr. Lewis is a Trustee of Clarkson University and New Hampton School. Mr. Lewis holds a B.S. from Clarkson College of Technology and has attended post-graduate programs at the University of Buffalo, Northeastern University and Harvard University. Mr. Lewis has a professional Director Certification, earned through an extended series of director education programs sponsored by the Corporate Directors Group. Mr. Lewis brings leadership, general management, and large public company operational, financial and corporate experience to our Board. Holdings: 48,445 shares     View Transactions Date Type Shares Traded Price Range 12/30/2011 Acquisition (Non Open Market) 632 n/a 09/30/2011 Acquisition (Non Open Market) 443 n/a 06/30/2011 Acquisition (Non Open Market) 204 n/a 03/01/2010 Option Execute 22,166 3.38 - 4.24
Craig W. Moore
Craig W. Moore, age 66, has served as a director of NxStage since 2002 and currently serves as chair of our Compensation Committee and a member of our Audit Committee. Mr. Moore is also a member of Board of Directors of ThermoGenesis and serves on their Audit and Compensation Committees. Previously, Mr. Moore served on the board of Biologic System Corp. from 1992 to 2006. From 1986 to 2001, Mr. Moore was Chairman of the Board of Directors and Chief Executive Officer at Everest Healthcare Services Corporation, a provider of dialysis to patients with renal failure. Since 2001, Mr. Moore has acted as a consultant to various companies in the healthcare services industry. From 1986 through 2001, Mr. Moore was President of Continental Health Care, Ltd., an extracorporeal services and supply company, and from 1990 through 2004, he was President of New York Dialysis Management, a dialysis management business. Mr. Moore also serves as a director on several private company boards. Mr. Moore brings leadership, corporate and dialysis services industry experience to our Board. Holdings: 63,387 shares     View Transactions Date Type Shares Traded Price Range 12/15/2011 Sell 10,000 17.25 09/14/2011 Option Execute 18,791 3.76 06/30/2011 Acquisition (Non Open Market) 488 n/a 05/25/2011 Disposition (Non Open Market) 8,373 18.11 05/25/2011 Option Execute 14,000 10.83 03/31/2011 Acquisition (Non Open Market) 489 n/a 12/31/2010 Acquisition (Non Open Market) 472 n/a 09/30/2010 Acquisition (Non Open Market) 615 n/a 07/27/2010 Sell 8,945 16.89 07/27/2010 Option Execute 12,000 12.59 06/30/2010 Acquisition (Non Open Market) 825 n/a 03/31/2010 Acquisition (Non Open Market) 1,026 n/a 12/31/2009 Acquisition (Non Open Market) 808 n/a
Reid S. Perper
Reid S. Perper, age 51, has served as a director of NxStage since September 2005 and currently serves as a member of our Audit Committee. Since September 2008, Mr. Perper has been a founder and partner of MCT Advisors LLP, a London based financial advisory firm. From January 2004 to March 2009, Mr. Perper was Managing Director of Healthcare Investment Partners LLC. From November 2000 through June 2003, Mr. Perper was a Managing Director and Co-Head of Europe for CSFB Private Equity. Prior to joining CSFB, Mr. Perper was a Managing Director of DLJ Merchant Banking Partners. Mr. Perper joined Donaldson, Lufkin & Jenrette in 1988. Mr. Perper also served as an investment professional for Caxton Europe Asset Management Ltd. from May 2004 through July 2005. Mr. Perper brings over 20 years of experience in private equity, as well as strategic and capital market experience, particularly within medical devices, healthcare services, pharmaceuticals and biotechnology, to our Board. Holdings: 93,173 shares     View Transactions Date Type Shares Traded Price Range 09/14/2011 Sell 30,000 18.84 - 19.55 08/31/2011 Sell 28,540 18.71 08/30/2011 Sell 30,000 18.44 08/29/2011 Sell 20,000 18.42 06/30/2011 Acquisition (Non Open Market) 392 n/a 05/25/2011 Disposition (Non Open Market) 4,187 18.11 05/25/2011 Option Execute 7,000 10.83 05/06/2011 Disposition (Non Open Market) 3,774 20.09 05/06/2011 Option Execute 7,000 10.83 03/31/2011 Acquisition (Non Open Market) 398 n/a 12/31/2010 Acquisition (Non Open Market) 351 n/a 09/30/2010 Acquisition (Non Open Market) 510 n/a 07/27/2010 Sell 8,945 16.89 07/27/2010 Option Execute 12,000 12.59 06/30/2010 Acquisition (Non Open Market) 724 n/a 03/31/2010 Acquisition (Non Open Market) 851 n/a 12/31/2009 Acquisition (Non Open Market) 1,167 n/a

= Chair of the Board = Chair = Member = Independent Director

Stock transaction information provided by EDGAR Online. NxStage Medical, Inc. makes no representation or warranty with respect to any of the information contained herein, takes no responsibility for supplementing, updating or correcting any such information and shall have no liability with respect to any such information. This listing does not include derivatives, such as stock option grants or shares purchased through an employee stock purchase plan. For recent transactions, including derivative transactions, see our Section 16 SEC filings page.