Exhibit 10.21 LOAN AND SECURITY AGREEMENT BORROWER: ATHENAHEALTH, INC., A DELAWARE CORPORATION ADDRESS: 311 ARSENAL STREET WATERTOWN, MASSACHUSETTS 02472 DATE: DECEMBER 28, 2005 This Loan and Security Agreement is entered into on the above date...Loan and Security Agreement • August 31st, 2007 • Athenahealth Inc • Services-business services, nec • California
