Patent Infringement Damages Calculator

Estimate patent infringement damages using lost profits and reasonable royalty methodologies.

⚖️ Legal📐 Patent Damages = Lost Profits OR Reasonable Royalty (whichever is higher)
Annual sales lost to infringement ($)
Profit margin on those sales (%)
Years of infringement
Reasonable royalty rate (%)
Please enter valid values.

Formula & Reference

VariableFormulaUnits
Patent Infringement Damages CalculatorPatent Damages = Lost Profits OR Reasonable Royalty (whichever is higher)$ estimate

Step-by-Step Examples

Example 1
3-Year Product Infringement

$500K annual sales, 40% margin, 3 years, 8% royalty rate.

  • Lost profits: $600K | Royalty: $120K
  • Damages: $600K | Willful: up to $1.8M
✓ $600K / up to $1.8M willful
Example 2
Software Patent

$2M annual sales, 25% margin, 2 years, 12% royalty.

  • Lost profits: $1M | Royalty: $480K
  • Damages: $1M
✓ $1M
Example 3
Small Infringement

$100K sales, 50% margin, 1 year, 10% royalty.

  • Lost profits: $50K | Royalty: $10K
  • Damages: $50K
✓ $50K

Real-World Applications

Common Mistakes to Avoid

⚠️
Lost profits require Panduit factors

To recover lost profits, patent holder must prove: demand for patented product, no acceptable substitutes, capacity to meet demand, and quantifiable lost profits (Panduit v. Stahlin).

⚠️
Reasonable royalty is the minimum

Even if lost profits can't be proven, the patent holder always gets at least a reasonable royalty (hypothetical negotiation standard, Georgia-Pacific factors).

Frequently Asked Questions

What is reasonable royalty?
The amount a willing licensor and licensee would have agreed to in a hypothetical negotiation at the time infringement began. Courts use the Georgia-Pacific 15-factor test.
Treble damages for willful infringement?
Courts may award up to 3× damages for willful or egregious infringement under 35 U.S.C. § 284.
Attorney fees in patent cases?
Available in 'exceptional cases' — those involving willful infringement or objectively unreasonable litigation positions.

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