In May 2015, we amended the lease for our corporate headquarters in Framingham, Massachusetts to
include approximately 12,500 square feet of additional office space. This lease is scheduled to expire in March 2021. Annual base rent for the additional space will be approximately $0.3 million, payable monthly starting in March 2016. Annual
base rent is subject to periodic increases beginning in 2018.
In May 2015, we issued $202.4 million principal amount of 1.75% convertible
senior notes due December 15, 2021 (the 2021 Notes), unless earlier repurchased, redeemed or converted. This included $118.2 million of 2021 Notes that were issued in exchange for $101.3 million aggregate principal amount of our
3.5% convertible senior notes due December 15, 2017 (the 2017 Notes). Subsequent to the exchange, the outstanding balance of 2017 Notes is $42.5 million, which is due December 15, 2017, unless the 2017 Notes are earlier
repurchased or converted. Interest on the 2021 Notes and 2017 Notes is payable semi-annually in arrears on June 15 and December 15 of each year. Based on the outstanding principal amounts of our 2021 Notes and 2017 Notes at
September 30, 2015, annual interest payments will be approximately $5.0 million.
Except as disclosed above, in the nine months ended
September 30, 2015, there were no material changes outside the ordinary course of business to our contractual obligations provided in Part II, Item 7, Managements Discussion and Analysis of Financial Condition and Results of
Operations, included in our 2014 Annual Report on Form 10-K filed with the SEC on March 2, 2015.