patent-infringement-analysis

# Patent Infringement Analysis

Produces a report evaluating whether an accused product or process infringes asserted patent claims, for litigation counsel, in-house teams, or technical experts.

## Prerequisites

Gather before starting:

1. **Asserted patent(s)** — specification, claims, file history, prosecution docs, amendments, office action responses
2. **Accused product/process** — specs, manuals, marketing materials, drawings, schematics, source code, reverse engineering reports
3. **Prior art** — patents, publications, technical standards relevant to the technology
4. **Asserted claims identified** — which independent and dependent claims are at issue

## Report Structure

### 1. Executive Summary

| Element | Content |
|---|---|
| Overall conclusion | Qualified: "strong likelihood," "probable," "unlikely," or "no infringement" |
| Per-claim assessment | Bottom-line for each independent claim and key dependents |
| Recommendations | Cease / license / litigate / design-around / post-grant proceedings |
| Critical risks | Willfulness exposure, SOL deadlines, related litigation |
| Key uncertainties | Ambiguous terms, missing technical info, unsettled legal questions |

### 2. Patent Overview

- **Bibliographic data** — number, title, dates (issue/filing/priority), inventors, assignee, family
- **Technical field** — problem, inventive concept, advantages over prior art
- **Prosecution highlights** — amendments, narrowing arguments, disclaimer/estoppel, canceled claims
- **Asserted claims** — dependency relationships, selection rationale
- **Patent status** — litigation history, post-grant proceedings, terminal disclaimers

### 3. Claim Construction

Apply **Phillips v. AWH Corp.** framework for each disputed term:

| Source | Analysis |
|---|---|
| Claim language | Ordinary meaning to POSITA; context from surrounding claims |
| Specification | Definitions, "as used herein," lexicography, consistent usage |
| Prosecution history | Amendments, distinguishing arguments, disclaimer/estoppel |
| Claim differentiation | Presume different claims have different scope |
| Extrinsic evidence | Expert testimony, dictionaries — less weight than intrinsic |

Output as:

| Claim Term | Proposed Construction | Support (col:ln or prosecution doc + page) |
|---|---|---|

Flag ambiguous terms with alternative constructions and outcome impact. For **§ 112(f) means-plus-function** limitations: identify function → corresponding structure in spec → equivalents.

### 4. Accused Product Description

- Product name, model, purpose, high-level operation
- Feature-by-feature description paralleling claim structure
- Cite evidence precisely: document title, page/section, figure, code file:line
- Note versions/configurations analyzed
- Flag non-observable features and information gaps needing discovery

### 5. Element-by-Element Infringement Analysis

For each asserted claim, produce a **claim chart**:

| # | Claim Limitation (as construed) | Accused Feature (with evidence) | Literal? | DOE? |
|---|---|---|---|---|

**Literal infringement**: Apply all-elements rule. Cite specific evidence for each correspondence. Explain *why* each feature meets the limitation — no conclusory statements.

**Doctrine of equivalents** (where not literally met): Apply function-way-result or insubstantial differences test. Check DOE limitations:

| Limitation | Test |
|---|---|
| Prosecution history estoppel | Amendment-based narrowing? Festo presumption of surrender |
| Vitiation | Would DOE eliminate the limitation? |
| Dedication to public | Disclosed but not claimed? Johnson & Johnston |
| All-limitations rule | Apply per-element, not to invention as a whole |

**Infringement theories** (as applicable):
- **Direct** (§ 271(a)) — single entity performs all limitations
- **Inducement** (§ 271(b)) — knowledge + specific intent + active inducement
- **Contributory** (§ 271(c)) — material component + no substantial non-infringing uses + knowledge

State per-claim infringement likelihood with qualification and basis.

### 6. Validity Considerations

Presumed valid (§ 282). Invalidity: clear and convincing (litigation) or preponderance (PTAB).

| Defense | Framework |
|---|---|
| Anticipation (§ 102) | Single reference with every limitation; element-by-element; check statutory bars |
| Obviousness (§ 103) | Graham factors; secondary considerations (commercial success, long-felt need, failure of others, copying) |
| Eligibility (§ 101) | Alice/Mayo two-step: abstract idea/natural phenomenon → inventive concept |
| § 112 defenses | Written description, enablement, definiteness |

Flag uncited prior art not before the examiner — these are strong IPR candidates.

### 7. Defenses, Risks, and Strategy

**Equitable defenses**: Laches, equitable estoppel, implied license, exhaustion/first sale, inequitable conduct.

**Damages**:

| Factor | Framework |
|---|---|
| Lost profits | Panduit four-factor test |
| Reasonable royalty | Georgia-Pacific factors; hypothetical negotiation |
| Apportionment | Entire market value rule; isolate patented feature value |
| Marking (§ 287) | Product marking status; pre-notice damages exposure |
| Enhanced damages | Willfulness risk; opinion of counsel value |

**Strategy**: Evaluate litigation cost/timeline, design-around feasibility, licensing range from comparables, IPR timing (one-year post-complaint deadline), venue under TC Heartland, and business impact.

### 8. Conclusion and Recommendations

- Synthesize per-claim likelihood integrating construction + analysis + validity
- Candid strengths/weaknesses assessment
- Prioritized next steps by urgency and cost
- Information gaps requiring investigation
- Time-sensitive actions: preservation, opinion of counsel, IPR deadlines

## Checks

- Maintain neutral, analytical tone — acknowledge both strengths and weaknesses
- Cite precisely: patent col:ln, prosecution doc date + page, product doc + section, cases in Bluebook
- Use `[VERIFY]` for any citation not confirmed from source materials
- Distinguish known evidence from areas needing further investigation
- Qualify all assessments based on evidence strength — never overstate
- For means-plus-function claims, always identify structure + equivalents (narrower scope than general DOE)
- Flag willfulness risk early when accused infringer has knowledge of patent