As to obviousness:
The Defendants challenge patent validity on the ground of obviousness. Obviousness is decided as a matter of law based on four basic factual inquiries, as set forth in Graham v. John Deere Co., 383 U.S. 1, 17–18 (1966), and elaborated in KSR International, Co. v. Teleflex Inc., 550 U.S. 398, 406– 07 (2007), viz., (1) the scope and content of the prior art, (2) the level of ordinary skill in the field of the invention, (3) the differences between the claimed subject matter and the prior art, and (4) any objective indicia of unobviousness, such as commercial success or long-felt need, or failure of others.
The Defendants identified as the closest prior art Euro- pean Patent Office Publication No. 0 367 895 of the Sandoz company (“Sandoz”), published May 16, 1990, which de- scribes numerous pyrimidine-based statin compounds, including a compound designated as Compound 1b. Com- pound 1b has two –CH3 (methyl) groups on the amino side chain, instead of one –CH3 and one –SO2CH3 group as in rosuvastatin.
As to "obvious to try":
We agree that “obvious to try” was negated by the gen- eral skepticism concerning pyrimidine-based statins, the fact that other pharmaceutical companies had abandoned this general structure, and the evidence that the prior art taught a preference not for hydrophilic substituents but for lipophilic substituents at the C2 position. See Takeda Chem. Indus., Ltd. v. Alphapharm Pty., 492 F.3d 1350, 1357 (Fed. Cir. 2007) (“[I]n cases involving new chemical compounds, it remains necessary to identify some reason that would have led a chemist to modify a known compound in a particular manner to establish prima facie obviousness of a new claimed compound.”).
The district court correctly held that patent invalidity on the ground of obviousness had not been shown for the compound rosuvastatin. That ruling is affirmed.
Judge Mayer dissented:
I respectfully dissent. There can be no infringement of U.S. Reissue Patent No. 37,314 (the “’314 patent”) because that patent is invalid for improper reissue. Reissue is available under 35 U.S.C. § 251 to rectify an “error” resulting from inadvertence, accident, or mistake. No such error was present in U.S. Patent No. 5,260,440 (the “’440 patent”), so there is no basis upon which it could properly be reissued. Furthermore, Shionogi Sei- yaku Kabushiki Kaisha (“Shionogi”) has forfeited the right to obtain reissue by its failure to exercise due dili- gence in seeking to rectify the alleged defect in the ’440 patent.