Patent Litigation · Remedies
Patent Damages Explained
When a patent is infringed, the court must award at least a reasonable royalty — and may award lost profits or treble damages for willful infringement. Here is how each measure works and how courts calculate them.
Key takeaways
- →The legal floor is a reasonable royalty — courts must award at least this even when actual damages are hard to prove.
- →Lost profits can be higher than a reasonable royalty, but require proving demand, no non-infringing alternatives, manufacturing capacity, and profit amount (Panduit test).
- →Treble damages (up to 3×) are available for willful infringement under the subjective Halo Electronics standard.
- →Without marking your products, you can only collect damages from the date the infringer had actual notice — potentially losing years of recovery.
- →Apportionment is the default — you must isolate the value of the patented feature, not use the entire product revenue as a base.
- →In design patent cases, an infringer's total profit from articles of manufacture can be awarded (§ 289) — this is different from utility patent damages.
The statute
35 U.S.C. § 284 — the damages provision
“Upon finding for the claimant the court shall award the claimant damages adequate to compensate for the infringement, but in no event less than a reasonable royalty for the use made of the invention by the infringer, together with interest and costs as fixed by the court. When the damages are not found by a jury, the court shall assess them. In either event the court may increase the damages up to three times the amount found or assessed.”
35 U.S.C. § 284
Three things follow from this language: (1) the court must award damages — it has no discretion to deny them if infringement is found; (2) a reasonable royalty is the floor, not a default — the patentee can elect lost profits if they are provable and higher; (3) up to 3× enhancement is available but not automatic — the court has discretion.
Compensatory measure
Reasonable Royalty
Minimum floor always available
Higher compensatory
Lost Profits
Requires Panduit test proof
Enhancement
Up to 3× (Treble)
Willful infringement only (Halo)
Design patents only
Infringer's Total Profit
§ 289, different standard
Measure 1
Reasonable royalty — the legal floor
A reasonable royalty is determined through a hypothetical negotiation: what royalty rate would the patent holder and the infringer have agreed to in an arm’s-length negotiation, just before infringement began, if both parties knew the patent was valid and infringed? Both parties are assumed to be rational negotiators who reach a deal.
The Georgia-Pacific Corp. v. U.S. Plywood Corp. (S.D.N.Y. 1970) decision established 15 factors courts and juries use to reconstruct this negotiation. Not all factors apply in every case, but damages experts typically address each one.
Apportionment: the default rule
The royalty base must be apportioned to reflect only the value of the patented feature, not the entire product revenue. The Federal Circuit significantly tightened the entire market value rule (EMVR) in Uniloc USA v. Microsoft(2011) and subsequent decisions — a patentee cannot use the full product price as the royalty base unless the patented feature is the sole driver of consumer demand. Modern damages experts isolate the patented feature’s incremental contribution using comparables, surveys, and technical analysis.
Measure 2
Lost profits — the Panduit test
A patent holder who would have made the infringer’s sales (or lost them to price erosion) can seek lost profits rather than — and in addition to in some cases — a reasonable royalty. Lost profits are typically larger but harder to prove.
The Panduit Corp. v. Stahlin Bros. Fibre Works (6th Cir. 1978) test requires proving four elements:
Demand for the patented product
There was actual consumer demand for a product embodying the patented invention during the infringement period.
Absence of acceptable non-infringing alternatives
The market had no acceptable non-infringing substitutes that purchasers would have chosen instead. If one exists, sales would not necessarily have gone to the patent holder.
Manufacturing and marketing capacity
The patent holder had the capacity (production, sales force, distribution) to make the additional sales they claim were lost.
Amount of lost profits
The specific dollar amount of profits lost — based on the patent holder's profit margin applied to the units the infringer sold.
Price erosion — the price reduction a patent holder had to make to compete with the infringing product — is also recoverable as part of lost profits, on top of lost unit sales.
Measure 3
Treble damages for willful infringement
Courts can increase damages up to three times the compensatory amount for willful infringement — but since Halo Electronics, Inc. v. Pulse Electronics, Inc. (Supreme Court, 2016), willfulness requires more than just knowledge of the patent. The standard is subjective and egregious: did the infringer act in a wanton, malicious, or bad-faith manner despite knowing of the patent?
Factors pointing to willfulness:
- Knowledge of the patent (through patent marking, demand letter, or prior litigation)
- Copying the patented product or process
- Continuing to infringe after receiving a cease-and-desist letter without seeking legal opinion
- Deliberate design-arounds that still infringe after being told of the risk
- False statements made during litigation (litigation misconduct)
Factors against willfulness:
- Good-faith, reasonable belief in non-infringement (freedom-to-operate opinion from counsel)
- Independent development — no copying
- Disputed patent validity raised in good faith
- Quick cessation of infringement once notified
- Novel legal question at the time of infringement
Enhanced damages are also discretionary — a finding of willfulness does not guarantee 3×. Courts weigh the overall egregiousness of the infringer’s conduct, litigation behavior, and the strength of any defenses.
Marking requirement
How marking affects your damages period
Under 35 U.S.C. § 287, if you make or sell articles embodying a patented invention, you must either physically mark those articles with the word “Patent” and the patent number, or use virtual marking (a URL directing users to a web page listing the patents covering the product). Without proper marking, you can only collect damages for infringement occurring after the infringer received actual notice — typically the filing of the lawsuit or a specific demand letter.
Without marking
Patent issued Jan 2020. Infringement began Feb 2020. Lawsuit filed Jun 2025. Damages period: June 2025 forward (actual notice date).
→ 5+ years of damages potentially forfeited
With proper marking
Patent issued Jan 2020. Products marked. Infringement began Feb 2020. Lawsuit filed Jun 2025. Damages period: February 2020 forward.
→ Full damages from first infringing act
Full guide: Patent Marking — How to Label Patented Products →
FAQ
Common questions about patent damages
What is the minimum amount of patent damages a court can award?
Under 35 U.S.C. § 284, the court shall award 'damages adequate to compensate for the infringement, but in no event less than a reasonable royalty for the use made of the invention.' A reasonable royalty is therefore the floor, not the ceiling. Courts establish this baseline through the hypothetical negotiation framework — what royalty the parties would have agreed to in an arm's-length negotiation just before infringement began. In practice, reasonable royalty verdicts in high-stakes cases have ranged from thousands of dollars to hundreds of millions.
What are the Georgia-Pacific factors for reasonable royalty?
The Georgia-Pacific Corp. v. U.S. Plywood Corp. (1970) decision established 15 factors courts use to determine a reasonable royalty: (1) existing royalties for the patent; (2) royalties for comparable patents; (3) nature and scope of the license; (4) licensor's licensing policy; (5) commercial relationship between licensor and licensee; (6) effect of the patent on selling other products; (7) duration of the patent and license; (8) established profitability of the product; (9) utility and advantages of the patented invention over alternatives; (10) nature of the patented invention and benefits to users; (11) extent of infringer's use; (12) customary profit from use; (13) portion of profit attributable to the invention vs other elements; (14) expert opinion; and (15) hypothetical negotiation result. Not all factors apply in every case.
What are treble damages in a patent case?
Under 35 U.S.C. § 284, a court may increase damages up to three times the compensatory amount — this is called treble (triple) damages. They are available only for willful infringement, and since the Supreme Court's 2016 Halo Electronics v. Pulse Electronics decision, courts use a subjective inquiry: did the infringer know of the patent and deliberately infringe it despite that knowledge? A 'wanton, malicious, and bad-faith' standard applies. Treble damages are not automatic even for willful infringement — courts weigh factors including the infringer's good-faith defenses, litigation conduct, and whether the infringer was a copyist.
How does patent marking affect damages?
Under 35 U.S.C. § 287, a patent owner who makes or sells patented articles must either physically mark those articles ('Patent' + patent number) or use virtual marking (a website listing patent numbers for products) to collect pre-notice damages. Without proper marking, damages can only be collected from the date the infringer received actual notice of infringement — typically the date of filing suit or a specific demand letter. Marking failure is a common, powerful defense in patent litigation that can dramatically reduce the damages period.
What is the entire market value rule in patent damages?
The entire market value rule (EMVR) allows a patent holder to base a reasonable royalty on the entire value of a product (not just the patented component) if the patented feature drives consumer demand for the entire product. Courts have significantly restricted EMVR since the Federal Circuit's Uniloc (2011) and VirnetX (2020) decisions — the patentee must show the patented feature is the basis for customer demand, not just a feature of the product. Apportionment — attributing the royalty base only to the incremental value of the patented feature — is now the default approach.