1 Exhibit 10.31 COMMON STOCK PURCHASE AGREEMENT This Common Stock Purchase Agreement (the "Agreement") is entered into as of ___________, 1997, by and among Transkaryotic Therapies, Inc., a Delaware corporation (the "Company") with its principal...Common Stock Purchase Agreement • July 29th, 1997 • Transkaryotic Therapies Inc • Biological products, (no disgnostic substances) • Massachusetts
