An element-by-element exercise, not an impression of similarity. One missing limitation ends that claim.
Start a conversation with the IP Concierge, already scoped to proving infringement. Pick a starting point, or describe the matter directly.
Infringement analysis is unglamorous and unforgiving. The asserted claim is broken into its limitations, and each one must be located in the accused product or process. Miss one and that claim fails, however closely the two things otherwise resemble each other. The evidence required varies enormously with the technology — source code review for software, circuit analysis and die imaging for semiconductors, testing and materials characterisation for mechanical and chemical inventions — but the structure never changes. What separates a strong technical case from a weak one is usually not sophistication but discipline: a claim chart that actually cites evidence for each limitation rather than restating the claim language with the product name substituted in.
The routes to infringement and the proof each one demands.
Every limitation present exactly as construed. The primary route, and the one that survives appeal most reliably.
Insubstantial differences, assessed limitation by limitation — not a general similarity test, and bounded by what prosecution surrendered.
For software claims, the code is the product. Reviews happen under protective order in controlled conditions.
Physical inspection, measurement and reverse engineering where documentation does not answer the question.
Inducement and contribution, which add knowledge and intent elements that documents rather than technology tend to prove.
Method claims may require showing the accused system was actually operated in the claimed way, not merely capable of it.
What the technical work product looks like when it is done properly.
Liability, and the shape of everything negotiated afterward.
The most common weakness in an infringement report is a chart whose right-hand column paraphrases the left-hand column with the accused product name inserted. It reads as thorough and proves nothing. Each limitation needs a citation to something that exists independently of the expert: a document, a line of code, a measurement, a test.
For direct infringement, generally no — it is a strict liability question, and a company can infringe a patent it has never heard of. Knowledge becomes central for indirect infringement, where inducement and contribution carry knowledge and intent requirements, and for willfulness, which affects whether damages can be enhanced. This is why notice letters and the internal responses to them become such heavily contested documents.
It depends on what kind of claim it is, and the distinction matters more than most clients expect. An apparatus claim may be infringed by a product configured to meet the limitations, whereas a method claim generally requires the method actually to be performed. That difference drives what has to be proved: for method claims the case often turns on evidence of how customers actually used the system, which means logs, manuals, defaults and support records rather than the technology itself.
Usually decisively. Marketing material and documentation describe intent; code describes behavior, and the two diverge often enough that an opinion resting only on documentation is fragile. Access is normally available in litigation under a protective order with strict conditions — a secured machine, no network, logged printing. The practical constraint is time: code review is slow, and cases are routinely scheduled as though it is not.
It is a genuine route and a narrower one than its reputation suggests. It is applied limitation by limitation rather than to the invention as a whole, and it is constrained by prosecution history and by the rule that it cannot be used to cover what the prior art already occupies. Treating it as a safety net for a weak literal case is usually a mistake; treating it as a considered alternative for one or two specific limitations is not.
Describe the claims and the accused product. The Institute will help you see what the proof requires.