Patent Strategy
Infringement Opinion
A freedom-to-operate opinion from qualified patent counsel is the primary defense against willful infringement claims — establishing a good-faith belief in non-infringement before or after a competitor's patent is identified.
What is a patent infringement opinion and what does it cover?
A patent infringement opinion (also called a freedom-to-operate or FTO opinion) is a formal written legal analysis prepared by a patent attorney assessing whether a specific product, process, or service infringes one or more specific patents.
Structure of an Opinion
(1) Identification of Subject Matter. Describes the product or process being analyzed
(2) Claim Construction. Interprets the language of each claim in the patent being analyzed, applying the broadest reasonable construction or the Philips standard used in district courts
(3) Limitation-by-limitation Comparison. Compares each element of each claim to the corresponding feature (or absence of feature) of the accused product
(4) Literal Infringement Analysis. Assesses whether each element reads literally on the product
(5) Doctrine of Equivalents Analysis. If literal infringement is not found, assesses whether equivalent elements are present (same function, way, result)
(6) Conclusion. States a conclusion about whether infringement is likely, possible, or unlikely
Types of Opinions
- Non-infringement opinion (element is missing, claim is not infringed)
- Invalidity opinion (patent is likely invalid)
- Unenforceability opinion (inequitable conduct, prosecution history issues)
Level of Certainty. Opinions typically express conclusions as 'strong non-infringement position,' 'reasonable non-infringement argument,' or 'infringement likely' — not absolute certainty
When Needed. Before product launch, before acquiring patent-encumbered technology, before entering a new market segment, when threatened with infringement, in connection with insurance
Qualified Author. Must be authored by a patent attorney (not just an attorney) — someone with technical training and USPTO registration.
How does an infringement opinion protect against willful infringement and enhanced damages?
The primary strategic purpose of an infringement opinion is to establish a defense against willful infringement claims and potential treble damages.
Enhanced Damages Statute. 35 U.S.C. § 284 authorizes courts to increase damages up to three times the amount found or assessed
Pre-halo Standard
- Seagate Technology (Fed. Cir. 2007) — two-part test requiring (1) objectively reckless standard of risk
- (2) subjective awareness of that risk
- Obtaining an opinion provided a strong defense to both prongs
- HALO ELECTRONICS, INC. v. PULSE ELECTRONICS (S.Ct. 2016): abolished the rigid Seagate test
- The Court held that 'willful' in § 284 means conduct that is 'deliberate or intentional' — not just reckless
- Enhanced damages should be reserved for 'egregious cases of misconduct beyond typical infringement'
- Subjective bad faith is the key inquiry
Current Standard. Willfulness is now a more subjective inquiry: did the infringer know about the patent? Did the infringer have a good-faith belief in non-infringement? Was the infringement deliberate, knowing, or wanton?
A Good-faith Opinion Helps
- A non-infringement opinion from qualified counsel demonstrates that the accused infringer: (a) knew about the patent
- (b) took steps to evaluate whether their product infringed
- (c) relied on a reasoned legal conclusion that it did not infringe
- This supports a finding that the infringement was not willful (not 'egregious misconduct')
Waiver of Privilege
- If a defendant invokes the opinion as a defense, they waive attorney-client privilege over the opinion and related communications
- Courts require producing the opinion, correspondence about it, and underlying work product.
How does attorney-client privilege apply to infringement opinions?
Attorney-client privilege protects infringement opinions from discovery, but asserting them as a defense triggers waiver.
Protected by Default
- An infringement opinion is attorney-client privileged if: (1) authored by a licensed attorney
- (2) prepared in the course of the attorney-client relationship
- (3) kept confidential
- (4) requested for legal advice (not business decisions)
What is Protected
- The opinion letter itself
- Oral advice from counsel about infringement
- Internal notes and draft opinions
- Communications between attorney and client about the opinion's conclusion
What is not Protected
- Underlying factual information (patent copies, product specs, prior art) — these are not privileged
- Communications that were disclosed to third parties
- Technical analysis disconnected from legal advice
Waiver by Assertion
- If the accused infringer invokes the opinion at trial as a defense to willfulness, they waive privilege over: the opinion itself
- All communications between counsel and client about the opinion
- Related work product
- Related legal advice on the same subject matter
- This is a significant strategic decision — the client must choose between keeping the opinion privileged (and potentially losing the willfulness defense) or waiving privilege to use the opinion defensively
- IN-HOUSE vs.
Outside Counsel
- Courts have sometimes given less weight to in-house counsel opinions, though formal privilege protection applies to both
- Outside counsel opinions are typically more persuasive to courts and juries
Draft Opinions
- Draft opinions may also be discoverable if the defendant waives privilege
- Often the final opinion and drafts are both produced.
What is the difference between an infringement opinion, a validity opinion, and a freedom-to-operate search?
These related but distinct legal services address different questions about patent risk.
Freedom-to-operate (FTO) Search
- A search for patents that might cover a planned product or process
- Searches multiple databases (USPTO, Espacenet, Google Patents) to identify potentially blocking patents
- Provides a LIST of patents to be analyzed — not itself an opinion on infringement
- Much broader in scope than an infringement opinion (which analyzes a specific patent)
Infringement Opinion
- A claim-by-claim legal analysis of whether a specific product infringes a SPECIFIC patent
- Requires detailed claim construction and technical comparison
- Narrower but deeper than an FTO search
- Answers: 'does our product infringe Patent X?'
- VALIDITY OPINION (also called INVALIDITY OPINION): analyzes whether a specific patent is valid — likely to be found invalid in litigation or IPR
- Covers § 102 anticipation (prior art that anticipates), § 103 obviousness, § 101 subject matter eligibility, § 112 written description/enablement
- Answers: 'is this patent likely invalid?'
- Often obtained together with an infringement opinion: if the product infringes, can we attack the patent's validity?
- FTO CLEARANCE vs.
Comprehensive Opinion
- A quick FTO clearance checks the identified patents broadly
- A formal opinion digs deeper into specific patents of concern
Combined Analysis
- Most sophisticated FTO opinions combine: (1) search for relevant patents
- (2) claim construction for patents of concern
- (3) non-infringement analysis for those patents
- (4) invalidity analysis for patents where infringement risk is elevated.
When should a company obtain an infringement opinion and what does it cost?
Practical guidance on when to commission an infringement opinion.
Timing — Before Product Launch
- The most important time to obtain an opinion
- Before any product containing the potentially infringing technology is made, used, or sold
- Obtaining an opinion AFTER launch does not eliminate willfulness for pre-opinion activity
Triggers for an Opinion
- (1) a competitor holds a patent in your technology space
- (2) you've received a cease-and-desist letter
- (3) a competitor has been sued for similar technology
- (4) you're designing a product around a specific patent
- (5) you're acquiring a company and conducting IP due diligence
- (6) your patent counsel identifies a blocking patent during prosecution
Cease-and-desist Letters
- Receiving a C&D letter puts you on notice of the patent
- From that point, continuing to make/sell without obtaining an opinion is evidence of willful infringement
Cost
- Simple opinion (one patent, straightforward technology): $5,000–$15,000
- Complex opinion (one patent, complex technology): $15,000–$50,000
- Comprehensive FTO study (many patents, new product): $50,000–$200,000+
- Costs increase with claim complexity, technical complexity, number of patents, and level of detail required
- PATENT RISK vs.
Opinion Cost
- When a product generates $1M+ annually, a $20,000 opinion is cost-effective
- When a product is a small side project, a full opinion may be disproportionate
Updates
- Opinions should be updated when: new patents issue
- The product design changes
- The patent owner amends claims in reexamination or continuation
- A court issues a claim construction ruling on the patent.
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