Pfizer and Teva started a bench trial on Wednesday over Pfizer's patents on sildenafil (Viagra), before Judge Smith in the Norfolk Division of the EDVA.  Pfizer has two patents on Viagra, one which expires in 2012, and a subsequent patent that extends to 2019.  Pfizer sued Teva for infringement, alleging that Teva's generic version of sildenafil, which it intends to market on March 27, 2012, upon expiration of the earlier patent, would infringe Pfizer's later patent.  Teva has asserted that the subsequent patent is invalid.  On the first day of trial, the parties presented this Joint Stipulation to the Court, where the parties stipulate to the facts that, of the two asserted claims, Teva's generic version does not directly infringe those claims, but does induce infringement of and contributorily infringe those claims, under the Court's claim construction.  The parties then proceeded to Teva's invalidity case.  With sales of Viagra at approximately $1 billion annually (potentially as high as $1.9 billion in 2009), needless to say the case is extremely important to both parties.

 Coverage of the case can be found at the WSJ, Fierce Pharma, and the Virginian Pilot