Section 282 of the Patent Act, 35 U.S.C. § 282, provides that a patent is presumed valid and places the “[t]he burden of establishing invalidity of a patent or any claim thereof . . . on the party asserting such invalidity.” Yesterday the Supreme Court granted certiorari in Microsoft Corp. v. i4i Limited Partnership, No. 10-290, to address the standard of proof in cases where a claim of invalidity is based on evidence not considered by the Patent and Trademark Office (PTO) in granting the patent. The question presented is whether, under such circumstances, the Federal Circuit erred when it held that an invalidity defense must be proved by clear and convincing evidence.

The resolution of this case is of interest to a broad range of patent holders and users, as demonstrated by the large number of amicus briefs filed in support of the petition. If the Court holds that invalidity need only be proven by a preponderance of the evidence, rather than by clear and convincing evidence, challenging patents will become easier, at least in cases involving evidence not considered by the PTO. The $290 million case is also of interest in its own right as it involves Microsoft’s popular Word program and the largest patent verdict ever affirmed by a circuit court.

Respondent i4i owned a patent for an improved method of storing and editing computer code. It sued Microsoft, alleging that Microsoft’s Word infringed i4i’s patent. In defense, Microsoft argued that prior art rendered the patent invalid because i4i included an implementation of the patent in a program i4i had sold more than one year before it applied for the patent at issue.

Since its creation in 1982, the Federal Circuit has consistently held that patent invalidity must be proved by clear and convincing evidence, a more exacting standard than proof by a mere preponderance of the evidence. Accordingly, the Federal Circuit rejected Microsoft’s contention that the imposition of the heightened “clear and convincing” standard is improper. However, application of that standard was called into question by dicta in the Supreme Court’s 2007 decision in KSR International Co. v. Teleflex, Inc., 550 U.S. 398 (2007). Although the Court’s decision on other grounds made it unnecessary to determine what quantum of proof is required to overcome § 282’s presumption of validity, the Court “note[d] that the rationale underlying the presumption—that the PTO, in its expertise, has approved the claim—seems much diminished” when evidence underlying the invalidity defense was never presented to the PTO. 550 U.S. at 426. Although that language could be viewed as an invitation to revisit its position, the Federal Circuit has continued to impose a heightened evidentiary standard under § 282. It has done so, moreover, despite the fact that prior to 1982 all twelve regional circuit courts had rejected or questioned the clear-and-convincing standard in cases where the grounds for invalidity were not considered by the PTO.

Absent extensions, amicus briefs in support of the petitioner will be due on January 20, 2011, and amicus briefs in support of the respondents will be due on February 21, 2011. Any questions about this case should be directed to Jeffrey Sarles (+1 312 701 7819) in our Chicago office.

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