The Federal Circuit warned against relying on conclusory expert
testimony in TQ Delta, LLC v. Cisco Sys., Inc.,
Nos. 2018-1766, 2018-1767 (Fed. Cir. Nov. 22, 2019).
In response to TQ Delta’s patent infringement suit, Cisco
filed two IPR petitions, challenging TQ Delta’s patents on
obviousness grounds. The Board instituted both proceedings
and found all the challenged claims obvious over the combination of
two prior art patents. TQ Delta appealed.
In reversing the Board, the Federal Circuit first noted that the
two prior art patents the Board relied on solved different problems
than that solved by TQ Delta’s patents. In making its
decision that it would be obvious to combine those patents, the
Board relied exclusively on the testimony of Cisco’s
expert. The Federal Circuit characterized the expert’s
testimony as “brief, high-level explanation” untethered
to any contemporaneous or supporting evidence. The Federal
Circuit thus reversed the Board’s obviousness