The Federal Circuit’s Evolving Obviousness Analysis

The Federal Circuit continues to take some of the bite out of the Supreme Court's KSR decision (KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007)) that broadened the basis for determining that patent claims are obvious by, among other things, avoiding overly rigorous application of the TSM (teaching, suggestion, motivation) test. In Unigene Labs. and Upsher-Smith Labs. v. Apotex (Fed. Cir. August 25, 2011) (available at http://www.cafc.uscourts.gov/images/stories/opinions-orders/10-1006.pdf), the Federal Circuit held that use of 20 mM citric acid as an absorption-enhancing agent and surfactant in a nasal spray composition was not obvious in view of the combination of an otherwise similar formulation using BZK (benzalkonium chloride) for that purpose and a reference using citric acid as a buffer in a nasal spray composition.