If You Are Sued, or You Sue
The short version
Nine decisions, and three of them are halves of pairs that have to be read whole. They cover what you forfeit by challenging a patent at the Patent Office, the gap between infringing on purpose and being punished for it, what makes a damages number admissible, and how far a U.S. patent reaches.
No half of any pair is published alone here, because on its own each one points a reader in a direction the law does not actually go.
Three of these decisions share a shape. In each pair, the first case creates an exposure and the second bounds it, and a reader who sees only one comes away with a confident belief that is wrong.
Estoppel. Caltech alone says inter partes review is a trap that forfeits every argument you did not make. Ingenico alone says estoppel barely matters. Neither is true. Estoppel is broad on document-based grounds and does not reach grounds an IPR could never have heard.
Willfulness. SRI alone says being found willful means paying multiples. Columbia alone says enhancement is nearly unobtainable. Together they say the real structure: a jury decides whether you infringed on purpose, a judge decides separately whether to punish you, and what the judge weighs is largely how you behaved after the suit was filed.
Foreign damages. Brumfield alone says a U.S. patent reaches revenue earned abroad. Columbia is where a patent owner tried that route and lost it on a jury instruction, with the doctrinal question left open. The framework applies; the causation still has to be proved.
Willfulness. SRI alone says being found willful means paying multiples. Columbia alone says enhancement is nearly unobtainable. Together they say the real structure: a jury decides whether you infringed on purpose, a judge decides separately whether to punish you, and what the judge weighs is largely how you behaved after the suit was filed.
Foreign damages. Brumfield alone says a U.S. patent reaches revenue earned abroad. Columbia is where a patent owner tried that route and lost it on a jury instruction, with the doctrinal question left open. The framework applies; the causation still has to be proved.
The Decisions
| Decision | Court | Decided | In one line |
|---|---|---|---|
| Caltech v. Broadcom | Federal Circuit | 4 February 2022 | If you challenge a patent at the Patent Office, you lose every printed-publication argument you could have raised and didn't. |
| Ingenico v. IOENGINE | Federal Circuit | 7 May 2025 | Losing an IPR does not bar you from proving the invention was already in public use, even using the same documents. |
| SRI v. Cisco | Federal Circuit | 28 September 2021 | Willfulness asks whether the infringement was deliberate, and enhanced damages do not automatically follow from it. |
| Columbia v. Gen Digital | Federal Circuit | 11 March 2026 | A technical improvement that lives only in your specification cannot save your claims, and software downloaded abroad is made abroad. |
| Hikma v. Amarin | Supreme Court | 4 June 2026 | What matters is whether you encouraged the infringing use, not whether a reader could take your words that way. |
| EcoFactor v. Google | Federal Circuit | 21 May 2025 | A royalty number pulled from a license's preamble, rather than its terms, is not evidence. |
| Brumfield v. IBG | Federal Circuit | 27 March 2024 | Foreign revenue can be reached by U.S. patent damages if domestic infringement caused it. |
| Lynk Labs v. Samsung | Federal Circuit | 14 January 2025 | A patent application that published after your invention can still be prior art against it, dated from when it was filed. |
| Socket Solutions v. Import Global | Federal Circuit | 4 August 2026 | Proving your patent is valid and infringed does not by itself get you an injunction. |
| VDPP v. Volkswagen | Federal Circuit | 19 August 2026 | If you licensed your patent and your licensees did not mark, your damages may start on the day you sued. |
Caltech v. Broadcom
The petition is a single, final opportunity to raise every patent and printed-publication argument, so the prior-art search has to be finished before you file.
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Ingenico v. IOENGINE
The same document can be estopped in one argument and freely usable in another. A launch email and an archived downloads page proved public use.
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SRI v. Cisco
Willfulness is not a heightened test requiring egregious conduct. Cisco lost because it had no reasonable defense, with no evidence of copying or concealment.
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Columbia v. Gen Digital
Every improvement Columbia identified was real, described in the patent, and absent from the claims. The $185 million judgment was vacated.
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Hikma v. Amarin
What matters is whether you encouraged the infringing use, not whether a reader could take your words that way. Encouragement can still be implicit.
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EcoFactor v. Google
A royalty number pulled from a license's preamble, rather than its terms, is not evidence. The lesson lands at signing time, not at trial.
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Brumfield v. IBG
Foreign revenue can be reached by U.S. patent damages if domestic infringement caused it. The framework applies; the causation still has to be proved.
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Lynk Labs v. Samsung
A published application is prior art from the day it was filed, under the pre-AIA statute. A search that filters by publication date can miss it.
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Socket Solutions v. Import Global
Proving your patent is valid and infringed does not by itself get you an injunction. Decided August 4, 2026, so check it is still current.
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VDPP v. Volkswagen
Marking is the cheapest way to lose money in patent law, and it reaches your licensees. Eleven settlement licences and no pleaded compliance cost the patentee its pre-suit damages.
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What These Pages Do Not Decide
- Whether to file an inter partes review, or what grounds a petition should raise. That is litigation strategy with forfeiture attached.
- Whether any particular conduct is willful, or whether any exposure is real.
- Whether a company should review third-party patents. No decision here addresses that question, and one of them is frequently misread as though it does.
- Whether any documentation, integration guide or tutorial induces infringement, whether your licenses support a royalty, whether your foreign revenue is exposed, or whether you could obtain an injunction. Each of those is a determination on specific facts.
Educational, not legal advice. Every quotation is verified against the court's own opinion. Consult a qualified patent attorney about your actual exposure.
Related
Patent Term and Double Patenting
Two Federal Circuit decisions that must be read together. One creates the exposure, the other bounds it, and acting on either alone costs term in opposite directions.
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Software Patents After Alice
Alice changed the rules, not the game. 58% of software patents still get approved. A guide to what survives, prosecution strategies, and what developers should document.
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Who Owns It, Who Invented It
Ownership and inventorship are different questions with different rules, and confusing them has destroyed patents. Three decisions mark the boundaries, each read from the opinion itself.
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What recent patent decisions add up to
Twenty-seven decisions, read from the opinions. The recurring theme is that patent law rewards specificity about mechanism and punishes description of results.
Read the Synthesis
VDPP v. Volkswagen
Marking is the cheapest way to lose money in patent law, and it reaches your licensees. Eleven settlement licences and no pleaded compliance cost the patentee its pre-suit damages.
Read the Case