Identify Weaknesses Opposing Expert Damages Report

Skill: Identify Weaknesses in Opposing Expert’s Damages Report

1. Subject-matter triage (only if applicable)

• Treat the report as a damages-opinion attack assignment, not a merits brief.
• Start by isolating the expert’s core assumptions: infringement date or negotiation date, damages theory, royalty base, royalty rate, apportionment logic, comparable licenses, and final number.
• Identify every distinct assumption or data source the expert relies on, then test each one separately before synthesizing the rebuttal.
• If the record supports only one damages model or one negotiation frame, say so expressly and explain why alternatives are unsupported.

2. Failure modes the skill is correcting

• Critiquing conclusions without separating methodological defects from impeachment points for cross-examination.
• Accepting the expert’s royalty base, rate, or apportionment structure without checking whether the evidentiary record supports each step.
• Comparing licenses only at a high level while ignoring technology scope, economic terms, litigation posture, timing, and bundled rights.
• Missing excluded comparables or cherry-picked selections that materially skew the analysis.
• Treating conversions between lump-sum and running-royalty structures as self-evident rather than examining the conversion method.
• Stating that an opinion is unreliable without tying the critique to the governing admissibility standard and the particular factual mismatch.

3. Legal frameworks / domain conventions that apply

• In patent damages, a reasonable royalty is framed by a hypothetical negotiation at the relevant time, with the damages analysis anchored to the parties’ positions and available information then.
• Under Federal Rule of Evidence 702 and the Daubert line of authority, the question is whether the expert used a reliable method and applied it reliably to the facts, not whether the opinion is merely plausible.
• Use the governing apportionment principles to test whether the asserted royalty base captures only the value attributable to the patented feature or instead sweeps in unrelated product value.
• Apply the entire market value rule cautiously: if the report uses full-product revenue, the analysis must show that the patented feature drives demand or that the chosen base is otherwise justified under the accepted damages framework.
• Comparable licenses should be tested for technological comparability, economic comparability, and structural comparability; licenses involving litigation pressure, different scope, different rights, or different consideration often require careful adjustment or exclusion.
• If the expert bridges between lump-sum and running-royalty forms, the conversion must be explained, grounded in the record, and consistent with the chosen royalty base.
• A damages critique should distinguish between a challenge that goes to admissibility and one that goes to weight, so the rebuttal memo can support both Daubert briefing and deposition or trial cross.

4. Analytical scaffolds

1. Identify the opinion architecture: theory of harm, relevant date, base, rate, apportionment approach, license set, and final damages figure.
2. Break the report into discrete propositions and test each proposition against the source materials.
3. For the royalty base, ask whether the expert relies on entire-product revenue, a component base, or another metric; then check whether the report explains why that base matches the patented contribution.
4. For apportionment, ask what feature or features are said to drive value, whether the method is disclosed, and whether the record supports the purported allocation.
5. For licenses, review each relied-upon agreement against the record evidence and identify exclusions, omissions, or mischaracterizations.
6. For every included license, test technological scope, economic terms, timing, negotiation context, and whether the expert made a disclosed and defensible adjustment.
7. If the expert relies on a smaller set of licenses than the record contains, assess whether the selection is justified or appears cherry-picked.
8. If the expert translates between different royalty structures, examine whether the conversion logic is transparent and grounded in accepted damages principles.
9. Evaluate which criticisms are best framed as Daubert defects, which are better used as weight arguments, and which can do both.
10. Tie each weakness to the practical consequence for the damages number, the admissibility challenge, or the credibility of the opinion.

5. Vertical / structural / temporal relationships (only if applicable)

• Track the relationship between the asserted negotiation date and the timing of each comparator license; older or later licenses may require an explanation for market changes.
• Track the relationship between product-level revenues, component revenues, and the patented feature’s incremental value.
• Track the relationship between license scope and the accused product’s scope; broader rights, cross-licenses, portfolio rights, or non-infringement considerations can distort comparability.
• Track the relationship between lump-sum payments and running royalties when the expert uses one form to infer the other.
• Track the relationship between factual developments in the record and the expert’s characterization of bargaining leverage, litigation pressure, or business context.
• When multiple comparables, assumptions, or product lines are involved, enumerate them before analysis and address each one directly rather than collapsing them into a single general critique.

6. Output structure conventions

• Write the memo as a rebuttal-oriented issue memorandum, organized by weaknesses in the damages opinion rather than by the order of the expert’s report.
• Use headings that naturally fit damages analysis, such as:
  • damages framework and governing standard
  • royalty base / market-value support
  • apportionment
  • comparable-license selection and treatment
  • royalty-rate derivation and conversions
  • factual mischaracterizations affecting the opinion
  • Daubert and cross-examination implications
• For each weakness, include:
  • the expert’s proposition,
  • the defect or omission,
  • the supporting source evidence,
  • whether it is primarily a Daubert issue, a weight issue, or both,
  • and the downstream effect on the damages opinion.
• Include controlling legal authority by name and rule when making legal propositions; do not leave admissibility or damages standards implicit.
• When useful, distinguish between:
  • exclusion arguments,
  • narrowing or limiting arguments,
  • and impeachment themes for deposition or trial.
• End with a concise Recommended Actions section that converts the critique into next steps for briefing and cross-examination, using imperative verbs and clear ownership.