Expert class library
The classes of expert witness that appear in litigation: what each is retained to answer, the methods they rely on, how their testimony is attacked under Rule 702, and how courts have ruled. A class is defined by role and method, never by a person or a firm. Every ruling was read in the opinion on CourtListener.
Securities
Market-model event study · Price impact rebuttal
Plaintiff event-study and loss-causation econometricianPlaintiff sideSingle-firm event study · Disaggregation of confounding information
Market-efficiency expertPlaintiff sideCammer factor analysis · Krogman factor analysis
Securities accounting and GAAP expertEither sideGAAP compliance review · Restatement analysis
Antitrust
Before-and-after regression · Benchmark or yardstick comparison
Plaintiff common-impact economistPlaintiff sidePricing structure analysis · Class-wide regression with impact dummies
Indirect-purchaser pass-through economistEither sidePass-through regression · Distribution chain mapping
Defense class-certification antitrust economistDefense sideUninjured class member analysis · Disaggregated regression testing
Market-definition economistEither sideHypothetical monopolist (SSNIP) test · Critical loss analysis
Exclusionary-conduct damages economistPlaintiff sideBut-for market share modeling · Yardstick and benchmark analysis
Labor-market antitrust economistPlaintiff sideCompensation structure analysis · Wage regression with conduct variables
Commercial
Before-and-after method · Yardstick method
Forensic accountantEither sideFund tracing · Financial statement reconstruction
Industry custom and practice expertEither sideTrade usage analysis · Contract term interpretation in context
Commercial damages rebuttal expertDefense sideAssumption sensitivity testing · Causation and alternative explanation analysis
Banking and lending standards expertEither sideUnderwriting guideline review · Loan file sampling
Intellectual property
Georgia-Pacific factor analysis · Comparable license analysis
Trademark likelihood-of-confusion survey expertEither sideEveready survey format · Squirt survey format
Patent lost-profits damages expertPlaintiff sidePanduit factor analysis · Market share approach
Defense patent damages expertDefense sideNon-infringing alternative analysis · Design-around cost estimation
Technical patent infringement expertPlaintiff sideElement-by-element claim comparison · Doctrine of equivalents analysis
Trade-secret damages expertPlaintiff sideUnjust enrichment calculation · Avoided cost and head-start analysis
Copyright damages and apportionment expertEither sideInfringer profits apportionment · Deductible expense analysis
Patent invalidity and prior-art expertDefense sideAnticipation analysis · Obviousness and motivation to combine
Mass tort and product liability
Bradford Hill causation analysis · Weight-of-the-evidence review
Specific-causation physicianPlaintiff sideDifferential etiology · Medical record review
Product design engineerPlaintiff sideAlternative design analysis · Failure mode analysis
Toxicologist (dose-response)Either sideDose-response assessment · Exposure reconstruction
Warnings and human factors expertEither sideWarning adequacy analysis · ANSI Z535 standards review
FDA regulatory expertEither sideRegulatory history review · Labeling change analysis
Personal injury
Momentum and energy analysis · Event data recorder download
Forensic economist (lost earnings)Either sideWorklife expectancy analysis · Earnings capacity projection
Biomechanical engineerDefense sideInjury mechanism analysis · Force and acceleration estimation
Life care plannerPlaintiff sideMedical needs assessment · Future care cost projection
Medical standard-of-care expertEither sideStandard of care comparison · Medical record review
Vocational rehabilitation expertEither sideTransferable skills analysis · Labor market survey
Employment
Multiple regression of pay or promotion · Standard deviation analysis
Wage-and-hour damages expertPlaintiff sideRepresentative sampling · Time and motion study
Defense labor economistDefense sideDisaggregated analysis by decision unit · Omitted variable testing
Industrial-organizational psychologistEither sideTest validation study · Job analysis
Consumer class actions
Choice-based conjoint survey · Willingness-to-pay estimation
Consumer perception survey expertEither sideConsumer perception survey · Materiality survey
Defense survey rebuttal expertDefense sideSurvey design critique · Control group testing
Hedonic regression price-premium economistPlaintiff sideHedonic regression · Product attribute coding
Insurance
Construction
Bankruptcy and valuation
For how to read these alongside the cases, see the guides, the sample brief and how it works. The library summarises public decisions for orientation; it is not legal advice. Read the opinion before relying on any ruling.