Case No. 05APP1433 (June 22, 2006). In a 31-page opinion, the Federal Circuit vacated the Northern District of Illinois's preliminary injunction against Kenyon & Kenyon client Teva USA's marketing of its generic equivalents of Abbott's Biaxin XL tablets, which have annual sales of more than $250 million. The court rejected the district court's conclusion with respect to the validity of two Abbott patents that cover the drug, holding that Teva USA had raised a "substantial question" with respect to the whether the patented inventions "would have been obvious."