ATLAS VENTURE PARALLEL FUND V-A C V

• 10% owner at ALNYLAM PHARMACEUTICALS, INC. · on record since Feb 27, 2006
• 10% owner at HELICOS BIOSCIENCES CORP · on record since May 31, 2007
• 10% owner at ACHILLION PHARMACEUTICALS INC · on record since Oct 25, 2006
• 10% owner at Isilon Systems, Inc. · on record since Dec 21, 2006
• 10% owner at MOMENTA PHARMACEUTICALS INC · on record since Jun 24, 2004
• 10% owner at PHASE FORWARD INC · on record since Jul 13, 2004
• 10% owner at NxStage Medical, Inc. · on record since Oct 27, 2005