Indian-based pharmaceutical manufacturer Lupin Ltd. has finally tasted the success of the knocking down King’s US Pat. 5,061,722 (the ‘722 patent) covering blockbuster drug Altace, generically known as Ramipril. The US Court of Appeals for the Federal Circuit ruled in the favor of Lupin holding that the ‘722 patent is invalid. Earlier, the US District Court for the District of Columbia concluded at summary judgment that claims of the ‘722 patent are valid and infringed by Lupin’s Abbreviated New Drug Application No. under the doctrine of equivalence. Accordingly Lupin appealed to Court of Appeals. The Court of Appeals invalidated the ‘722 patent over obviousness holding that claims 1 and 2 of the ‘722 patent are invalid over the SCH 31925 mixture (referring to work conducted by Dr. Smith), the US Pat. 5,348,944, and the enalapril references in the prior art.