Realtime Data LLC v. Actian Corporation, 6:15-cv-00463

Realtime Data, LLC sued Riverbed for patent infringement; experts Dr. Arthur Keller (technical) and Robert Mills (damages) previously had apportionment opinions partially struck by the Court.
The Court earlier found Keller’s methodology failed to account for the combined benefit of two compression elements and ruled Mills could not simply adopt Keller’s technical "value" as the final apportionment.
Riverbed moved to strike Keller’s and Mills’s supplemental reports, arguing Mills still relies entirely on Keller, Keller’s analysis captures non‑patented functionality, and the supplemental opinions contradict earlier opinions.
Realtime defended the supplements: Keller limited his analysis to technical benefits and measured incremental benefit of the dual compression; Mills used Keller only as an input and independently reviewed Riverbed documents and market data.
The Court evaluated the admissibility under Daubert (relevance and reliability) and considered whether inconsistencies went to admissibility or weight.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether Mills unlawfully relies solely on Keller for apportionment	Mills uses Keller only as an input and independently analyzes Riverbed documents and market factors	Mills continues to rely entirely on Keller’s apportionment analysis	Denied — Mills’ independent review and market analysis provide sufficient basis beyond Keller
Whether Keller’s analysis improperly captures non‑patented functionality	Keller measures incremental technical benefit of dual compression over single compression and limits to technical value	Keller’s quantitative analysis includes non‑patented features and overstates patented contribution	Denied — Keller’s technical analysis is properly limited and challenges go to weight, not admissibility
Whether Keller’s supplemental opinions contradict his original report such that they must be struck	Supplemental opinions build on and emphasize prior points; any inconsistencies affect weight	Supplemental report materially contradicts earlier report and is unreliable	Denied — differences do not warrant exclusion; not sufficiently contradictory
Whether the experts’ apportionment opinions satisfy Daubert relevance and reliability	Experts’ methods are reliable and applicable to facts in issue	Methods are unreliable and improperly applied	Denied — court finds both experts’ opinions sufficiently reliable and relevant to survive Daubert

Daubert v. Merrell Dow Pharms., 509 U.S. 579 (trial judge must ensure expert testimony rests on a reliable foundation and is relevant)
Johnson v. Arkema, Inc., 685 F.3d 452 (5th Cir.) (expert relevance requires methodology applicable to facts in issue)
Curtis v. M & S Petroleum, Inc., 174 F.3d 661 (5th Cir.) (expert reliability standard; more than unsupported speculation)