The US Court of Appeals for the Federal Circuit found that the defendant failed to sufficiently allege any prejudice caused by alleged errors relating to claim construction, and affirmed the district court’s application of prejudgment interest beginning at the date of the hypothetical negotiation determined for calculating damages. Comcast IP Holdings I LLC v. Sprint Comm’ns Co., Case No. 15-1992 (Fed. Cir., Mar. 7, 2017) (Chen, J).

The patents at issue are generally directed to the use of computer network technology to facilitate a telephone call. There was no dispute among the parties as to how the accused call flows operate. A jury found that Sprint’s handling of certain phone calls infringed various claims of Comcast’s patents, and awarded Comcast $7.5 million in damages. The district court denied Sprint’s motion for judgment as a matter of law or a new trial, and added prejudgment interest to the damages award, starting from the time of the hypothetical negotiation on which the jury based its damages award. 

Sprint appealed, challenging the construction of three claim terms as well as the district court’s application of prejudgment interest. Sprint challenged the jury’s finding of infringement, arguing that the term “switched telecommunication system” should have been more narrowly construed to exclude any element of a datagram-based system. The Federal Circuit found Sprint’s argument both unpersuasive and irrelevant because Sprint did not demonstrated any prejudicial error. The Court concluded that even if Sprint’s contention regarding the claim construction was correct, given the evidence presented, the jury would have found that Sprint infringed the relevant claims, so there was no prejudicial error.

Sprint also challenged the jury’s finding that the “call destination” limitation was met by the relevant accused call flows. Because neither party asked for a construction of this term, the jury was instructed to construe it according to its plain and ordinary meaning. The Federal Circuit found it improper for Sprint to proffer a claim construction argument on appeal in the guise of a challenge to the sufficiency of the evidence of infringement. Further, the Court found that Sprint had not shown that it had the only reasonable view of the claim limitation. The jury reasonably relied on expert testimony to construe this term according to its plain and ordinary meaning. Thus, the Court found that substantial evidence supported the jury’s finding on this point.

Sprint further challenged the district court’s construction of the term “parsing.” The Federal Circuit concluded that Sprint had waived this argument by not presenting any argument in its opening brief as to how its purportedly correct and narrower claim construction would have affected the infringement verdict, i.e., prejudice. Notwithstanding the waiver, the Court agreed with the district court’s construction finding no prosecution history disclaimer. For prosecution disclaimer to attach, the alleged disavowing actions or statements made during prosecution must be both clear and unmistakable. Here, the Court found the prosecution history ambiguous with respect to the challenged claim term.

Lastly, Sprint challenged the district court’s application of the prejudgment interest from 2006 going forward because neither of the patents at issue had issued at that point. The Federal Circuit disagreed, finding that the district court properly awarded prejudgment interest running from the date of the earliest relevant hypothetical negotiations, which both experts agreed would have occurred in 2006. Because this was the only damages award for the district court to consider when assessing the dollar figure against which to measure prejudgment interest, the Court found that the district court’s assessment of prejudgment interest was not an abuse of discretion.