Q1 2026 Patent Daubert Digest

Q1 2026 patent Daubert rulings held the pattern that has been in place since the FRE 702 amendment took effect: most motions denied, a substantial minority granted in part, a small share granted in full. The court concentration tightened slightly. Damages experts continued to draw the largest share of motions in the wake of EcoFactor. The expert-side noise in patent litigation is now consistent enough quarter over quarter that variance from the baseline is worth paying attention to when it appears.

This digest reports the baseline and flags what is moving.

Volume and outcomes

Patent-related Daubert motions decided on the merits in Q1 2026 split roughly 51% denied, 35% granted in part, 14% granted in full. The numbers match the 2025 full-year aggregate to within a percentage point. The partial-to-full ratio held at about 2:1, meaning the modal exclusion order is one that trims an expert's testimony at specific opinions rather than excluding the expert outright.

Total volume is roughly flat against Q1 2025 and Q1 2024. There is no sign of a Daubert-motion surge or contraction. What has changed since 2023 is the length and specificity of the orders. District courts are writing through the FRE 702 amendment's evidentiary standard with citations to it. Pre-amendment shorthand ("goes to the weight, not the admissibility") is rarer.

Court concentration

Four districts accounted for the majority of patent Daubert rulings in Q1 2026: the Eastern District of Texas, the District of Delaware, the Northern District of California, and the Northern District of Illinois. The concentration tracks the patent caseload concentration. Within that group, Delaware and the Eastern District of Texas produced the longest opinions, with detailed reliability findings that other courts have begun to cite.

The Western District of Texas, dominant in patent filings several years ago, continued to produce a smaller share of Q1 Daubert rulings than its filing volume would suggest. The transfer pattern from 2023 and 2024 is still working through the docket.

Technical experts versus damages experts

Damages expert motions accounted for the plurality of Q1 2026 Daubert rulings, continuing the post-EcoFactor pattern. EcoFactor (en banc, 2025) sharpened the methodology requirements for reasonable-royalty opinions, and district courts have read the decision as authorizing closer scrutiny of the analytical chain a damages expert walks through.

The grant-in-part rate for damages expert motions ran slightly above the overall rate in Q1 2026. The most common exclusion grounds were apportionment methodology, comparable-license selection, and the use of pre-suit conduct as a Georgia-Pacific factor without methodological support.

Technical expert motions were the second-largest category. Exclusion grounds clustered around obviousness opinions that did not walk through the secondary-considerations evidence, claim-construction opinions that crossed the line into legal conclusion, and infringement opinions that relied on attorney-supplied infringement theories without independent technical analysis.

PTAB-experienced experts appeared on both sides of Q1 motions. Cross-references between PTAB credibility findings and district court Daubert briefing are visible in the longer opinions. A pattern of adverse PTAB credibility findings is now a citable input on a Daubert challenge.

What is changing at the margin

A few signals are worth tracking out of Q1.

First, courts are citing EcoFactor for the proposition that the damages expert's analytical chain has to be documented step by step, with the underlying data accessible. The citation is being applied to comparable-license analysis specifically, not just to apportionment.

Second, the rate at which obviousness opinions are challenged at Daubert (as opposed to argued through cross-examination at trial) has ticked up slightly. The challenges are typically targeted at the absence of secondary-considerations engagement.

Third, motions targeting source-code review depth in software cases have appeared more frequently. The argument is that an expert who has reviewed a small fraction of the accused code cannot opine reliably on the operation of the accused system. The motions are not consistently granted. They are increasingly written.

Fourth, the Federal Circuit's most consequential Q1 expert-testimony decision was Barry v. DePuy Synthes Cos., a precedential panel ruling that reversed the mid-trial exclusion of two patent experts and held that methodological criticisms generally go to weight rather than admissibility. The dissent read the decision as pulling against EcoFactor's gatekeeping framework. An en banc rehearing petition is pending. The doctrinal arc set by EcoFactor and Rex Medical in 2025 is now contested, not extended.

Practical implications

Retaining partners working motions in Q2 2026 should assume the baseline holds. The modal outcome is denial. The next-most-likely outcome is grant in part. Briefing should be built around the specific opinions worth excluding, not against the expert as a whole. Damages expert motions remain the highest-yield target by category. Technical expert motions on obviousness should engage the secondary-considerations record directly.

A note on the data

The figures in this digest are aggregated from district court Daubert orders involving patent expert witnesses on WitnessLens, filtered to motions decided on the merits in Q1 2026. Court concentration is computed by ruling volume rather than by case-filing volume. Case citations are to published Federal Circuit decisions. Methodology details are on the methodology page.