Intellectual Property > IP Newsflash > Allegedly Cumulative Prior Art Does Not Create An Estoppel Under 35 U.S.C. 315(e)(2)
24 Mar '16

Clearlamp, LLC filed a patent infringement action against LKQ Corporation (LKQ), who, in turn, counterclaimed seeking declaratory judgments of noninfringement and invalidity. During the pendency of this case, the parties participated in an inter partes review (IPR), during which the Patent Trial and Appeal Board found that several claims of the patent-at-issue were unpatentable as obvious in view of three prior art references. In the instant opinion, the Court grants LKQ’s motion for summary judgment on invalidity and denies the parties’ remaining motions on validity and noninfringement. The key issue addressed by the Court in deciding these summary judgment motions was whether LKQ was estopped under 35 U.S.C. § 315(e)(2) from combining the datasheet of a prior art product, which was not raised during the IPR proceeding, with the three prior art references used to invalidate other patent claims.

The court examined the language of § 315(e)(2) and interpreted the phrase “reasonably could have been raised” to mean that the scope of estoppel applies to “prior art which a skilled searcher conducting a diligent search reasonably could have been expected to discover.” However, rather than establishing that a skilled search would have found the product’s datasheet, Clearlamp argued that a skilled search would have found cumulative pieces of prior art. The Court rejected Clearlamp’s argument and found that cumulative prior art does not invoke § 315(e)(2) estoppel. Therefore, LKQ could rely on the product’s datasheet combined with the three prior art references to establish the asserted claims were obvious.

Clearlamp, LLC v. LKQ Corp., No. 12-cv-2533 (N.D. Ill. Mar. 18, 2016).