Lease Arrangements

We have entered into various long-term non-cancelable operating leases for equipment and facilities. We lease facilities in Foster City, Fremont, Palo Alto and San Dimas, California; Branford, Connecticut; Princeton, New Jersey; Seattle, Washington; the Dublin and Cork areas of Ireland and the London area of the United Kingdom. We also have operating leases for sales, marketing and administrative facilities in Europe, Canada and Asia Pacific. Our leases expire on various dates between 2012 and 2030, with many of our leases containing options to renew. Certain facility leases also contain rent escalation clauses. Our most significant lease, related to a facility in Seattle, Washington, expires in 2020 and has a 10-year term. The lease provides us with three consecutive rights to extend the term of the lease through 2035 and contains an annual three percent rent escalation clause. The lease also requires us to pay additional amounts for operating expenses and maintenance. We also have leases for three corporate aircraft, with varying terms, with renewal options upon expiration of the lease terms.

Lease expense under our operating leases was approximately $48.1 million, $41.7 million and $37.3 million during the years ended December 31, 2011, 2010 and 2009, respectively. Aggregate non-cancelable future minimum rental payments under operating leases are as follows (in thousands):

Legal Proceedings

In June 2011, we received a subpoena from the United States Attorney's Office for the Northern District of California requesting documents related to the manufacture, and related quality and distribution practices, of Atripla, Emtriva, Hepsera, Letairis, Truvada, Viread and Complera. We have been cooperating and will continue to cooperate with this governmental inquiry. An estimate of a possible loss or range of losses cannot be determined given we are at the early stage of the inquiry.

We are a party to various legal actions that arose in the ordinary course of our business. We do not believe that any of these legal actions will have a material adverse impact on our consolidated business, financial position or results of operations.

Other Commitments

In the normal course of business, we enter into various firm purchase commitments primarily related to active pharmaceutical ingredients and certain inventory related items. As of December 31, 2011, these commitments for the next five years were approximately $990.2 million in 2012, $119.9 million in 2013, $82.6 million in 2014, $64.6 million in 2015 and $60.7 million in 2016. The amounts related to active pharmaceutical ingredients represent minimum purchase requirements. Actual payments for the purchases related to these active pharmaceutical ingredients were $1.53 billion, $835.7 million and $1.03 billion during the years ended December 31, 2011, 2010 and 2009, respectively.