The complete working map of the field: what each measure actually measures, the facts that point to it, what it demands in records, and where it gets attacked.
Damages is not one method with variations. It is a large family of distinct measures, each answering a different economic question, each with its own evidentiary demands and its own well-worn line of attack. Most reference material treats them one at a time, inside the practice area that uses them, which is why a litigator can be expert in three of them and unaware that a fourth fits their facts better. This page is the whole map in one place. It is the same taxonomy the Institute’s concierge works from, published rather than kept internal, because a reference that only we can see is worth less than one counsel can check us against.
73 models, 28 sources across 21 of them
Grouped by family. Where a model has a full treatment on this site, its name links to it. Where it does not, the entry here is the reference: enough to recognise the model on the facts, know what it would demand, and know what the other side will say about it. The literature listed under each is the foundational work, cited so you can go to the source rather than take our word for it.
Core measures of loss
The principal ways a loss can be measured at all. Most disputes begin by choosing among these, and the choice is usually made by habit.
Profits the plaintiff would have earned but for the conduct, less profits actually earned.
When
A trading business lost revenue over a bounded period and then recovered, or would have.
Requires
Historical financials at monthly granularity, cost detail fine enough to separate fixed from variable, pre-dispute budgets and pipelines.
Attacked on
The counterfactual is speculative, and the incremental cost deduction is too small.
Expertise
Forensic accountant or economist.
Foundational literature
Anton, J. J. & Yao, D. A. (2006). Finding "Lost" Profits: An Equilibrium Analysis of Patent Infringement Damages. Journal of Law, Economics, and Organization, 23(1), 186-207. https://doi.org/10.1093/jleo/ewm008Models how lost-profits awards depend on the but-for competitive equilibrium.
The position the plaintiff would have occupied had the contract been performed.
When
A contract was breached and the plaintiff wants the value of full performance.
Requires
The contract terms, the performance actually rendered, and evidence of the value promised.
Attacked on
The expected benefit was speculative, or foreseeability and certainty are contested.
Expertise
Forensic accountant or economist.
Foundational literature
Rogerson, William P. (1984). Efficient Reliance and Damage Measures for Breach of Contract. The RAND Journal of Economics, 15(1), 39. https://doi.org/10.2307/3003668Compares expectation, reliance and restitution measures on efficiency grounds.
Spier, Kathryn E. & Whinston, Michael D. (1995). On the Efficiency of Privately Stipulated Damages for Breach of Contract: Entry Barriers, Reliance, and Renegotiation. The RAND Journal of Economics, 26(2), 180. https://doi.org/10.2307/2555912Analyses stipulated damages against the expectation baseline.
Reliance damages
Expenditures wasted in reliance on the promise, restoring the plaintiff to its pre-contract position.
When
Expectation damages cannot be proven with certainty, often because the venture had no track record.
Requires
Documented outlays made in reliance, and evidence they were wasted rather than salvaged.
Attacked on
The expenditures would have been lost anyway because the venture would have failed regardless.
Expertise
Forensic accountant.
Foundational literature
Fuller, L. L. & Perdue, William R. (1936). The Reliance Interest in Contract Damages: 1. The Yale Law Journal, 46(1), 52. https://doi.org/10.2307/791632The article that named and separated the expectation, reliance and restitution interests.
Restitution and quantum meruit
The value of the benefit conferred on the defendant, rather than the plaintiff’s loss.
When
No enforceable contract, or the plaintiff performed and wants the reasonable value of that performance.
Requires
Evidence of the work performed and market rates for it, or the value received by the defendant.
Attacked on
The benefit was worth less than claimed, or was never actually conferred.
Expertise
Industry or valuation expert, sometimes a forensic accountant.
Out-of-pocket loss
The difference between what was paid and the true value of what was received.
When
A misrepresentation induced a transaction, commonly in fraud and securities matters.
Requires
The transaction price and a valuation of what was actually received at the transaction date.
Attacked on
The true value is contested, and later declines are attributed to other causes.
Expertise
Valuation or financial economist.
Liquidated damages provisions
Not a measure of loss but a contractual stipulation of it, tested against anticipated harm.
When
The contract fixes a sum, and the fight is whether it is a reasonable forecast or an unenforceable penalty.
Requires
Evidence of the harm anticipated at contracting, and the difficulty of estimating it then.
Attacked on
The stipulated sum bears no relationship to any harm actually anticipated.
Expertise
Economist, on the reasonableness of the ex ante estimate.
Foundational literature
Goetz, Charles J. & Scott, Robert E. (1977). Liquidated Damages, Penalties and the Just Compensation Principle: Some Notes on an Enforcement Model and a Theory of Efficient Breach. Columbia Law Review, 77(4), 554. https://doi.org/10.2307/1121823The economic case for enforcing stipulated damages, and the limits of the penalty rule.
Building the counterfactual
Every measure above rests on a world that did not happen. These are the methods for constructing it, and the discipline of separating the conduct from everything else that moved.
How the gap between plaintiff and comparator changed when the conduct began.
When
Both plaintiff and comparator were exposed to the same shocks, and only the plaintiff was exposed to the conduct.
Requires
Panel data on both, spanning before and during.
Attacked on
The parallel trends assumption: the two were already diverging.
Expertise
Econometrician.
Foundational literature
Bertrand, M., Duflo, E., & Mullainathan, S. (2004). How Much Should We Trust Differences-In-Differences Estimates?. The Quarterly Journal of Economics, 119(1), 249-275. https://doi.org/10.1162/003355304772839588Showed conventional standard errors badly overstate significance under serial correlation.
Goodman-Bacon, Andrew (2021). Difference-in-differences with variation in treatment timing. Journal of Econometrics, 225(2), 254-277. https://doi.org/10.1016/j.jeconom.2021.03.014Decomposes staggered-timing estimates and shows when they mislead.
The share of the observed loss attributable to the conduct rather than to everything else.
When
The market moved, a competitor entered, or the plaintiff stumbled during the damages period.
Requires
Market and industry data, competitor timing evidence, and controls or explicit carve-outs.
Attacked on
The all-or-nothing attribution, which is the classic ground for exclusion.
Expertise
Econometrician or economist.
Foundational literature
Rapp, Robert N. (2014). Plausible Cause: Exploring the Limits of Loss Causation in Pleading and Proving Market Fraud Claims Under Securities Exchange Act Section 10(b) and SEC Rule 10b-5. SSRN Electronic Journal. https://doi.org/10.2139/ssrn.2374378On separating fraud-related decline from everything else.
Measures that arise from the structure of a bargain: what substitute performance cost, what flowed downstream, and what a terminated relationship was worth.
Cover and market-price differential
The difference between the contract price and the cost of substitute goods, or the market price at breach.
When
A goods contract was breached and the buyer covered, or the seller resold.
Requires
The contract price, the cover or resale transactions, and market price evidence at the relevant time and place.
Attacked on
The cover was not reasonable or not made in good faith, or the wrong market price was used.
Expertise
Industry expert or forensic accountant.
Lost volume seller
The profit on the lost sale, even though the goods were resold to another buyer.
When
The seller had capacity to serve both the breaching buyer and the replacement buyer.
Requires
Evidence of surplus capacity and that the second sale would have happened anyway.
Attacked on
The seller was capacity constrained, so the resale genuinely replaced the lost sale.
Expertise
Economist or forensic accountant.
Foundational literature
Goldberg, Victor Paul (2018). The Lost Volume Seller In English Law. SSRN Electronic Journal. https://doi.org/10.2139/ssrn.3279823Examines whether the lost-volume theory holds up economically.
Consequential and incidental damages
Losses flowing from the breach beyond the value of the promised performance itself.
When
The breach caused downstream harm: lost customers, idle plant, extra freight, cover costs.
Requires
A causal chain documented from the breach to each downstream cost.
Attacked on
Foreseeability, contractual exclusions of consequential damages, and remoteness.
Expertise
Forensic accountant.
Franchise and dealer termination
The value of the terminated relationship: lost profits over the remaining term, or the value of the dealership.
When
A distributor, dealer or franchisee was terminated, often under a statute governing the relationship.
Requires
The relationship’s financial history, the remaining term, and evidence on renewal expectancy.
Attacked on
The relationship would not have been renewed, and the terminated party failed to mitigate.
Expertise
Industry economist or valuation specialist.
Foundational literature
(1964). The Elusive Measure of Damages for Wrongful Termination of Automobile Dealership Franchises. The Yale Law Journal, 74(2), 354. https://doi.org/10.2307/794786Early analysis of how terminated-relationship value is measured.
Lender liability and financing damages
The harm from credit wrongly denied, withdrawn, or supplied on wrongful terms.
When
A lender pulled a facility or breached a commitment and the borrower’s business suffered.
Requires
Evidence the borrower could have obtained replacement financing, and at what cost.
Attacked on
The business was failing regardless, and the borrower could have refinanced elsewhere.
Expertise
Financial economist.
Construction and delay
A field with its own vocabulary and its own named methods, because construction disputes turn on productivity and schedule rather than on lost sales.
Measured mile
Lost productivity, by comparing an unimpacted period of the same work to the impacted period.
When
A contractor claims disruption made the same work less efficient, and clean and impacted periods both exist.
Requires
Production records granular enough to isolate a genuinely unimpacted stretch of comparable work.
Attacked on
The chosen mile is not comparable, or was itself affected.
Expertise
Construction claims expert with scheduling and cost engineering depth.
Total cost and modified total cost
Actual costs less the bid, treating the excess as the damage; the modified version adjusts for bid error and contractor-caused overruns.
When
No clean measured mile is available and costs simply ran far beyond the bid.
Requires
A defensible bid, proof that other causes of overrun have been removed, and complete cost records.
Attacked on
It is disfavoured precisely because it assumes every overrun was the owner’s fault, including a bad bid.
Expertise
Construction claims expert.
Extended home office overhead (Eichleay)
Unabsorbed home office overhead during an owner-caused suspension or delay.
When
Work was suspended or delayed, the contractor was on standby, and could not take replacement work.
Requires
Proof of standby, the delay period, and the overhead allocation.
Attacked on
The contractor was not truly on standby, or could have taken other work.
Expertise
Construction claims expert or forensic accountant.
Delay, acceleration and cumulative impact
The cost of finishing late, of being forced to finish on time anyway, or of many changes compounding.
When
Schedule disputes: critical path delays, constructive acceleration, or a change order series with compounding effect.
Requires
Baseline and as-built schedules, a critical path analysis, and change order records.
Attacked on
Concurrent delay caused by the contractor, and schedule analyses that select their own method.
Expertise
Scheduling expert plus a damages expert.
Insurance and business interruption
First-party claims, where the policy rather than tort principle defines what is measured and over what period.
Business interruption
Lost earnings or profits during the period the policy covers, defined by the policy rather than by tort principles.
When
A covered peril halted or reduced operations and a first-party policy responds.
Requires
Pre-loss financials, the policy’s own definitions, and the period of restoration.
Attacked on
The period of restoration is shorter than claimed, and the projection ignores market conditions that would have hurt anyway.
Expertise
Forensic accountant with insurance claims experience.
Extra expense and expediting costs
Additional costs incurred to keep operating or to shorten the interruption.
When
The insured spent to mitigate: temporary premises, overtime, expedited freight.
Requires
Invoices tied to the mitigation, and a showing the spending reduced the loss.
Attacked on
The expense was not extra, or did not actually reduce the interruption loss.
Expertise
Forensic accountant.
Contingent business interruption
Loss caused by damage to a supplier or customer rather than to the insured’s own property.
When
A supply chain or key customer disruption flows through to the insured.
Requires
Dependency evidence, and a causal chain traced through the supply relationship.
Attacked on
Alternative suppliers were available, and the dependency was not as tight as claimed.
Expertise
Forensic accountant plus supply chain analysis.
Actual cash value and replacement cost
The cost to replace damaged property, with or without deduction for depreciation.
When
A property loss where the policy or the law sets which basis applies.
Requires
Replacement cost estimates and a depreciation analysis.
Attacked on
Depreciation method and useful life, and whether replacement actually occurred.
Expertise
Appraiser or cost estimator.
Intellectual property
The most engineered damages doctrine in the law, with dedicated structures that exist nowhere else and failure modes that are known in advance.
What a willing licensor and licensee would have agreed on the eve of infringement.
When
Patent infringement where lost profits cannot be proven, or the patent holder does not practise the patent.
Requires
Comparable licenses, the parties’ licensing histories, profitability data, and non-infringing alternatives.
Attacked on
The comparables are not comparable, and the rate is asserted rather than derived.
Expertise
Economist with patent damages depth, often with a licensing background.
Foundational literature
Sidak, J. Gregory (2018). Using Regression Analysis of Observed Licenses to Calculate a Reasonable Royalty for Patent Infringement. https://doi.org/10.2139/ssrn.3179157Derives a royalty from observed licenses adjusted for validity probability.
Sidak, J. Gregory & Skog, Jeremy (2018). Using Conjoint Analysis to Apportion Patent Damages. https://doi.org/10.2139/ssrn.3176717How conjoint evidence bears on the royalty base and apportionment.
The share of a product’s value attributable to the patented feature rather than to everything around it.
When
A multi-component product where the invention is one contributor among many.
Requires
Evidence isolating the feature’s contribution: conjoint or survey work, price differences, purchasing-decision documents.
Attacked on
The base swallowed the whole product, or the apportionment was asserted without evidence.
Expertise
Economist plus, often, a survey specialist.
Foundational literature
Sidak, J. Gregory & Skog, Jeremy (2018). Using Conjoint Analysis to Apportion Patent Damages. https://doi.org/10.2139/ssrn.3176717Applies survey evidence to isolate the patented feature's contribution.
A royalty consistent with a commitment to license on fair, reasonable and non-discriminatory terms.
When
The patent is declared essential to a standard and subject to a licensing commitment.
Requires
Comparable SEP licenses, portfolio strength evidence, and a separation of the technology’s value from the value of standardisation.
Attacked on
Royalty stacking, non-discrimination across licensees, and failure to separate standardisation value.
Expertise
Economist with SEP and standards experience.
Foundational literature
Sidak, J. Gregory (2018). The Value of a Standard Versus the Value of Standardization. https://doi.org/10.2139/ssrn.3176681Separates the value of the technology from the value of adopting a standard.
Measures built on the difference between the price that was paid and the price competition would have produced, and on where in the chain the harm landed.
How much of an overcharge each level of the distribution chain passed to the next.
When
Indirect purchaser claims, or a defence that the direct purchaser passed the overcharge on.
Requires
Intermediary pricing and margin records, and documented cost shocks to estimate the rate.
Attacked on
The estimated rate ignores market structure, or the analysis is asymmetric.
Expertise
Econometrician.
Foundational literature
Verboven, Frank & Dijk, Theon van (2007). Cartel Damages Claims and the Passing-On Defense. SSRN Electronic Journal. https://doi.org/10.2139/ssrn.1024469Formalises how overcharges pass down the chain and what that implies for claims.
Whether a security’s price moved abnormally on a disclosure date, beyond what the market and industry explain.
When
Any securities matter: efficiency, price impact, loss causation, and damages all run through it.
Requires
Daily price data, market and industry indices, a clean estimation window, and the disclosure record.
Attacked on
Specification choices made after seeing results, and confounding news on the same day.
Expertise
Financial economist with securities litigation experience.
Foundational literature
Brown, Stephen J. & Warner, Jerold B. (1985). Using daily stock returns. Journal of Financial Economics, 14(1), 3-31. https://doi.org/10.1016/0304-405x(85)90042-xEstablished the daily-returns methodology and its power properties.
Fama, Eugene F., Fisher, Lawrence, Jensen, Michael C., & Roll, Richard (1969). The Adjustment of Stock Prices to New Information. International Economic Review, 10(1), 1. https://doi.org/10.2307/2525569The original event study, and the source of the efficient-market framing.
The share of a price decline caused by the truth emerging rather than by everything else.
When
The stock fell on a day when the market fell, the sector rotated, or unrelated bad news also landed.
Requires
The full information record on each key date, and market and industry controls.
Attacked on
The decline is attributed entirely to the fraud despite obvious confounds.
Expertise
Financial economist.
Foundational literature
Rapp, Robert N. (2014). Plausible Cause: Exploring the Limits of Loss Causation in Pleading and Proving Market Fraud Claims Under Securities Exchange Act Section 10(b) and SEC Rule 10b-5. SSRN Electronic Journal. https://doi.org/10.2139/ssrn.2374378On the boundary between market movement and actionable loss.
The expected remaining years of labour force participation, exits and re-entries included.
When
Any individual claim projecting earnings over a career.
Requires
Published worklife tables matched to the person’s cohort, plus their own attachment record.
Attacked on
Departures from the statistical baseline that are asserted rather than argued.
Expertise
Forensic economist.
Foundational literature
Skoog, Gary R. & Ciecka, James E. (2006). Worklife Expectancy via Competing Risks/Multiple Decrement Theory with an Application to Railroad Workers. Journal of Forensic Economics, 19(3), 243-260. https://doi.org/10.5085/0898-5510-19.3.243Applies competing-risks theory to worklife estimation.
Ciecka, James E. & Skoog, Gary R. (2017). Expected Labor Force Activity and Retirement Behavior by Age, Gender, and Labor Force History. Statistics and Public Policy, 4(1), 1-8. https://doi.org/10.1080/2330443x.2017.1358125Extends worklife to second-order models using labour force history.
An economic valuation of the lost enjoyment of life itself, derived from willingness-to-pay studies.
When
Raised occasionally in injury and death matters. ⚠️ Admissibility is widely contested and it is excluded in many courts.
Requires
Value-of-statistical-life literature, which is contested in this application.
Attacked on
The methodology is heavily criticised, and many courts reject it outright.
Expertise
Economist, but counsel should confirm admissibility in the forum before commissioning it.
Foundational literature
Kniesner, Thomas J., Viscusi, W. Kip, Woock, Christopher, & Ziliak, James P. (2012). The Value of a Statistical Life: Evidence from Panel Data. Review of Economics and Statistics, 94(1), 74-87. https://doi.org/10.1162/rest_a_00229Panel estimates that narrow the VSL range hedonic claims rely on.
Cameron, Trudy Ann (2010). Euthanizing the Value of a Statistical Life. Review of Environmental Economics and Policy, 4(2), 161-178. https://doi.org/10.1093/reep/req010Critique of the VSL construct and how it is communicated.
Class and aggregate
Proving loss for many claimants at once, where the damages model is not only a calculation but the gate the case has to pass through.
The value consumers place on a specific product attribute, from choices among varied alternatives.
When
A consumer claim about a misrepresented or omitted feature, where the premium must be valued.
Requires
A survey design with realistic attributes, levels and prices.
Attacked on
Willingness to pay is a demand-side measure and does not by itself equal a market price effect.
Expertise
Survey and marketing science specialist plus a damages economist.
Foundational literature
Green, Paul E. & Srinivasan, V. (1978). Conjoint Analysis in Consumer Research: Issues and Outlook. Journal of Consumer Research, 5(2), 103-123. https://doi.org/10.1086/208721The survey that established conjoint practice in consumer research.
Green, Paul E. & Krieger, Abba M. (1993). Chapter 10 Conjoint analysis with product-positioning applications. Handbooks in Operations Research and Management Science, 467-515. https://doi.org/10.1016/s0927-0507(05)80033-7Later synthesis of conjoint methods and their limits.
The portion of the price attributable to the misrepresented claim.
When
Consumer class actions over labelling, certification or product claims.
Requires
Market pricing data across products with and without the claim, or survey evidence.
Attacked on
Comparator products differ in other ways, and supply-side factors are ignored.
Expertise
Economist with consumer market experience.
Property and environmental
Measures for harm to land, resources and reputation, where the loss is often persistent and the remedy is contested.
Diminution in value against cost of repair
The property’s loss in market value, or the cost to restore it, whichever the law permits.
When
Property damage, construction defect, or contamination affecting real property.
Requires
Appraisals before and after, and repair or remediation estimates.
Attacked on
Repair cost grossly exceeds the value lost, or the repair does not restore full value.
Expertise
Appraiser plus a remediation cost estimator.
Stigma damages
Residual loss in value that persists after remediation is complete.
When
Contamination or a notorious defect leaves the market wary even once the problem is fixed.
Requires
Paired sales analysis or hedonic regression showing a persistent discount.
Attacked on
The discount is temporary, or reflects factors other than the stigma.
Expertise
Real estate economist with hedonic modelling capability.
Natural resource damages
The public loss from injury to a natural resource, and the restoration needed to offset it.
When
Government trustee claims following a spill or contamination event.
Requires
Habitat or resource equivalency analysis, and restoration project costing.
Attacked on
The scaling of restoration to injury, and the discount rate applied over long horizons.
Expertise
Environmental economist with equivalency analysis experience.
Foundational literature
Dunford, Richard W., Ginn, Thomas C., & Desvousges, William H. (2004). The use of habitat equivalency analysis in natural resource damage assessments. Ecological Economics, 48(1), 49-70. https://doi.org/10.1016/j.ecolecon.2003.07.011Sets out the scaling logic behind resource-equivalency restoration claims.
Loss of goodwill and reputational harm
The economic value of damage to reputation or customer relationships.
When
Defamation, disparagement, or conduct that drove customers away.
Requires
Customer retention data, revenue patterns around the event, and market evidence.
Attacked on
Causation: customers left for other reasons, and reputational effects are inherently speculative.
Expertise
Economist, sometimes with survey support.
Adjustments and machinery
What runs after the measure is chosen. The least glamorous part of the field and, per dollar of award, among the most consequential.
Benefits and savings the conduct incidentally produced, and third-party payments.
When
Costs were avoided on sales never made, or insurance paid part of the loss.
Requires
A causal link from the conduct to each claimed benefit, and the applicable collateral source rule.
Attacked on
Legitimate offsets omitted, which damages credibility beyond the dollars.
Expertise
Forensic accountant.
Foundational literature
Fleming, John G. (1983). The Collateral Source Rule and Contract Damages. California Law Review, 71(1), 56. https://doi.org/10.2307/3480140Classic treatment of when third-party payments reduce recovery.
Tell me about the dispute: what happened, what economic harm is alleged, and roughly over what period. I'll help you see which of these models the facts could actually support. I won't compute a number or tell you what is legally recoverable.