Claim Construction Checklist: Term Selection, the Intrinsic Record, and Proposed Constructions

By Casey Scott McKay · 2024-01-18

Claim construction decides most patent cases and it is worked on a schedule that starts months before the hearing. This checklist runs it in thirteen phases: build the disclaimer table from the file wrapper, map the specification, chart every candidate construction against both infringement and invalidity, select terms by dispositiveness, decide the record, comply with local rules, exchange and build the joint chart, prepare or decline an expert, brief indefiniteness in parallel, brief the construction in the framework order, prepare the tutorial, argue, and act on the order. Each box gives the reason, the authority, and the trap. A worked matter runs throughout. The companion article supplies the doctrine and the companion guide the strategy.

IP and Technology > Patent Litigation | Checklist | Published 18 January 2024 - Updated 11 March 2025 | Casey Scott McKay - marksy.us

Summary. Claim construction decides most patent cases and it is worked on a schedule that starts months before the hearing. This checklist runs it in thirteen phases: build the disclaimer table from the file wrapper, map the specification, chart every candidate construction against both infringement and invalidity, select terms by dispositiveness, decide the record, comply with local rules, exchange and build the joint chart, prepare or decline an expert, brief indefiniteness in parallel, brief the construction in the framework order, prepare the tutorial, argue, and act on the order. Each box gives the reason, the authority, and the trap. A worked matter runs throughout. The companion article supplies the doctrine and the companion guide the strategy.

Keywords: claim construction checklist, disclaimer table, term selection, dual consequence charting, intrinsic record, prosecution history, lexicography, disavowal, claim differentiation, means plus function, indefiniteness, joint claim construction chart, construction expert, technology tutorial, Markman hearing, fallback construction, summary judgment, stipulated judgment, PTAB coordination, appellate preservation

How to use this checklist

| Phase | What it covers | When | |---|---|---| | 1 | Build the disclaimer table | Week one | | 2 | Map the specification | Weeks one to three | | 3 | Chart both consequences | Before proposing anything | | 4 | Select terms | At the exchange | | 5 | Decide the record | First month | | 6 | Comply with local rules | Continuous | | 7 | Exchange and build the joint chart | Per schedule | | 8 | Prepare or decline an expert | Per schedule | | 9 | Brief indefiniteness | With construction | | 10 | Brief the construction | Per schedule | | 11 | Prepare the tutorial | Before the hearing | | 12 | Argue | The hearing | | 13 | Act on the order | Days after |

Phases 1 through 3 determine the quality of everything downstream and are the ones most often compressed. Boxes marked [Gate] should clear before the next phase begins.

The matter. Two patents, eleven asserted claims, a court limit of five terms, and a parallel inter partes review filed by the same defendant. The boxes below follow it from file wrapper to stipulated judgment.

Phase 1. Build the disclaimer table

[ ] [Gate] Read the entire file wrapper before the specification.
- Why. The specification says what the invention is; the prosecution history says what the applicant already gave up, and concessions are the shortest route to a dispositive construction.
- Trap. Deferring the reading because it is voluminous, which is how dispositive arguments go unfound.
[ ] Record every narrowing amendment and the rejection it answered.
- Why. A narrowing amendment for patentability constrains construction and triggers estoppel limiting equivalents.
- Authority. 35 U.S.C. § 132(a) bars new matter; the amendment record is the estoppel record.
[ ] Record every argument distinguishing a reference, quoted in full.
- Why. Prosecution disclaimer requires a clear and unmistakable surrender, and the assessment turns on the full passage.
- Trap. Recording a paraphrase, which loses the argument either way.
[ ] Read the whole family, not only the patent in suit.
- Why. Disclaimer can arise from a parent, a continuation, or a sibling sharing the specification.
- Authority. 35 U.S.C. § 120 creates the shared record.
[ ] Read any post-grant record.
- Why. Statements at the Board are quoted in district court, and inter partes review applies the same construction standard.
- Authority. 35 U.S.C. § 311.
[ ] Check for terminal disclaimers.
- Authority. 37 C.F.R. § 1.321. They affect expiry and condition enforceability on common ownership.
[ ] Staff this to someone senior enough to recognize a surrender.
- Trap. A junior chronology, which is not the same work product as a disclaimer table.

Phase 2. Map the specification

[ ] Locate every claim term in the description.
- Trap. A term in the claims and nowhere in the specification — both a written description problem and a construction opportunity.
[ ] Find any express definition.
- Why. Lexicography controls over ordinary meaning and requires a clear expression of intent to define, not a description of an embodiment.
[ ] Find disavowal candidates.
- Why. Emphatic characterizations of "the invention," repeated disparagement of an alternative, and statements that a feature is essential, critical, or required.
- Trap. Treating consistent description of one embodiment as disavowal. It is not.
[ ] Count the embodiments per element.
- Why. One embodiment invites an importing-limitations argument; several defeat it.
[ ] [Gate] Locate the algorithm for every functional limitation, or confirm there is none.
- Why. For a computer-implemented function, the corresponding structure is the algorithm, not the processor. No algorithm means indefiniteness rather than narrowing.
- Authority. 35 U.S.C. § 112(f); 35 U.S.C. § 112(b).
- Trap. Accepting a block diagram as structure. See The Bargain of Disclosure.
[ ] Check terms of degree for an objective baseline.
- Trap. "Substantially," "about," "sufficient" with nothing in the specification to measure against.

Phase 3. Chart both consequences

[ ] [Gate] For every candidate construction, answer two questions: does the accused product meet the limitation, and does the prior art?
- Why. This is the pincer. A patentee arguing for breadth invites invalidity; a defendant arguing for narrowness may concede validity.
- Authority. 35 U.S.C. § 102; 35 U.S.C. § 103; 35 U.S.C. § 271(a).
- Trap. Charting infringement alone, which is how patentees construct their own invalidity case.
[ ] Build one table: term, construction, infringement consequence, invalidity consequence, confidence.
[ ] Do this jointly with whoever handles invalidity.
- Trap. Separate teams, so the pincer is invisible to both.
[ ] Rank by dispositiveness.
- Why. For each construction, what happens if you win it? If the answer is not "the case ends" or "the case improves materially," the term is decoration.
[ ] Complete this before proposing anything.
- Trap. Constructions proposed and later abandoned on validity grounds, which costs credibility that is hard to recover.

Phase 4. Select terms

[ ] Count the court's limit and propose fewer.
- Why. Three genuinely dispositive disputes persuade more than twelve, three of which matter.
[ ] For the defendant, select terms where narrowing produces non-infringement.
- Trap. Selecting a term because it is ambiguous rather than because winning it ends the case.
[ ] For the patentee, select terms where the opponent's construction creates a validity exposure.
[ ] Prefer terms appearing in every asserted independent claim.
- Why. A win there reaches the whole case.
[ ] Prefer terms with intrinsic support.
- Why. Intrinsic arguments beat extrinsic ones, and extrinsic evidence cannot contradict a clear intrinsic record.
[ ] Evaluate the preamble separately.
- Why. Whether it limits depends on whether it recites essential structure or merely states purpose, and it sometimes decides the case alone.
[ ] Offer to stipulate on the rest, prominently.
- Why. It concentrates the court's attention and it is noticed.
- Trap. Preserving every argument reflexively.

Phase 5. Decide the record

[ ] [Gate] Choose intrinsic-only or extrinsic, deliberately, in the first month.
- Why. The ultimate construction is reviewed without deference; subsidiary factual findings from extrinsic evidence are reviewed for clear error. The choice sets the appellate posture.
- Trap. Making it by default, which most cases do.
[ ] Choose intrinsic where you expect to appeal.
[ ] Choose extrinsic where you are confident below and want deference.
[ ] Confirm the intrinsic record is genuinely ambiguous before adding an expert.
- Why. Extrinsic evidence cannot contradict a clear intrinsic record, so the expert is wasted where the record is clear.
[ ] Budget the expert as a real line item.

Phase 6. Comply with local rules

[ ] Determine whether local patent rules govern, and diary every exchange.
- Trap. A rule district treated as an ordinary scheduling order.
[ ] Serve infringement and invalidity contentions carefully.
- Why. In rule districts they are served early and amended only on good cause, and careless contentions bind for the case.
- Authority. See Patent Infringement Contention Checklist.
[ ] Note term limits, page limits, and evidence disclosure deadlines.
- Trap. Extrinsic evidence excluded because it was not identified on schedule.
[ ] Read the judge's prior construction orders.
- Why. Format preferences, tutorial practice, and treatment of extrinsic evidence are knowable and rarely researched.

Phase 7. Exchange and build the joint chart

[ ] Propose a construction for every term you identify.
- Trap. "Plain and ordinary meaning" with no content, which is a legitimate position stated uselessly.
[ ] [Gate] Prepare a fallback construction for each term.
- Why. A party proposing one extreme position and refusing alternatives frequently receives a third construction suiting neither side.
[ ] Cite intrinsic support by column and line, or paragraph.
- Trap. A citation dump in the support column.
[ ] List agreed constructions prominently.
[ ] Flag indefiniteness contentions where the rules permit.
[ ] Meet and confer to narrow genuinely.
- Why. Courts notice which parties use the process and which perform it.

Phase 8. Prepare or decline the expert

[ ] Define the level of ordinary skill in the art explicitly.
- Why. Every opinion rests on it and the parties frequently propose different levels.
- Trap. An expert report that never states it.
[ ] Tie every opinion to the relevant date.
- Why. Meaning is assessed at the time of the invention, not today.
[ ] Confirm no opinion contradicts a clear intrinsic record.
- Trap. An opinion that will be disregarded and that undermines the rest of the testimony.
[ ] Comply with disclosure obligations.
- Authority. Fed. R. Civ. P. 26; admissibility under Fed. R. Evid. 702 and Fed. R. Evid. 703.
[ ] Prepare for the deposition questions that matter.
- Why. What the specification would have conveyed, whether the prosecution statement was a disclaimer, and whether the claim informs with reasonable certainty.

Phase 9. Brief indefiniteness in parallel

[ ] Identify the four target categories.
- Why. Terms of degree with no baseline, subjective terms, means-plus-function limitations with no structure, and claims mixing statutory classes.
- Authority. 35 U.S.C. § 112(b).
[ ] Run the software attack systematically.
- Why. Identify every functional limitation, argue 35 U.S.C. § 112(f) applies because the term is a nonce word, then argue no algorithm was disclosed. Either the claim narrows to a flowchart or it fails.
- Trap. Assuming the provision applies only where "means" appears.
[ ] Account for the burden.
- Authority. 35 U.S.C. § 282. Courts are cautious about invalidating where a construction is available.
[ ] Note the forum allocation.
- Why. Indefiniteness cannot be raised in an inter partes review under 35 U.S.C. § 311(b); it can be raised in a post-grant review within nine months under 35 U.S.C. § 321(c), and always in court.

Phase 10. Brief the construction

[ ] Brief in the framework's order: claims, other claims, specification, prosecution history, then extrinsic.
- Why. A brief performing the analysis in order gives the judge a path to a defensible opinion.
[ ] Invoke claim differentiation where a dependent claim answers the question.
[ ] [Gate] Never argue embodiments limit a claim without naming lexicography or disavowal.
- Why. It is the most common briefing error and courts identify it immediately.
[ ] Quote prosecution statements in full with their context.
- Trap. A truncated quotation that opposing counsel completes.
[ ] Address the opponent's strongest point, not the weakest.
[ ] Keep it short.

Phase 11. Prepare the tutorial

[ ] Find out the format from the judge's prior cases.
- Why. Live, video, joint, separate, with or without experts — practices vary widely.
[ ] Teach, do not argue.
- Trap. A tutorial that advocates, which is counterproductive and noticed.
[ ] Use the patent's own figures.
[ ] Keep it short and concrete.
[ ] Have the person who will argue deliver it.
- Trap. Delegating it as background, when it is the judge's first exposure and the credibility carries into the argument.

Phase 12. Argue

[ ] Lead with the dispositive term.
[ ] Know the record without notes.
- Why. Answering "where in the specification" and "what did the applicant say" immediately is what distinguishes construction argument.
[ ] Prepare the answer to the question that reveals the ruling.
- Why. In most hearings the judge asks one question showing where the decision is heading.
[ ] Offer the fallback when the primary position is not landing.
[ ] Answer honestly what turns on the dispute.
- Trap. Evasion, which judges notice.

Phase 13. Act on the order

[ ] Read it for what was decided and what was left at plain meaning.
- Trap. A term left unconstrued is still in dispute at trial.
[ ] [Gate] File the dispositive motion within days.
- Authority. Fed. R. Civ. P. 56.
- Trap. Drafting it after the order rather than before.
[ ] Consider a stipulated judgment where the construction is dispositive.
- Why. It gets the construction to the Federal Circuit directly rather than after trying a determined case.
- Authority. 28 U.S.C. § 1295.
[ ] Re-run damages.
- Why. A narrowed construction narrows the accused functionality and the royalty base.
- Authority. 35 U.S.C. § 284. See Patent Damages Checklist.
[ ] Re-run invalidity.
[ ] Preserve every argument for appeal.
- Trap. Constructions not proposed below are generally unavailable on appeal.
[ ] Update the settlement position honestly.

Outcome. Four terms selected from fourteen candidates, seven stipulated. The disclaimer table produced the dispositive argument on the first term. The second patent's sole independent claim was held indefinite for want of a disclosed algorithm. The construction order was followed within four days by a motion drafted before the hearing, and the parties then entered a stipulated judgment so the patentee could appeal the construction directly.

Phase 14. Coordinating with a parallel Board proceeding

[ ] [Gate] Appoint one owner of the construction position across every forum.
- Why. Inter partes review construes claims under the same standard as district court, which makes every statement in one forum evidence in the other.
- Authority. 35 U.S.C. § 311.
- Trap. Separate teams with different incentives — one avoiding prior art, one seeking infringement — producing inconsistent records that are worth more to the opponent than either team's arguments.
[ ] Circulate every filing in either proceeding to the team handling the other before it goes out.
- Trap. A patent owner preliminary response arguing for a narrow construction, filed without the district court team seeing it.
[ ] Track the one-year bar.
- Authority. 35 U.S.C. § 315(b). A petition must be filed within one year of service of an infringement complaint.
[ ] Plan the ground allocation deliberately.
- Why. Prior art to the Board under 35 U.S.C. § 311(b); indefiniteness, eligibility, and Section 112 to the district court, or to a post-grant review within nine months under 35 U.S.C. § 321(c).
- Trap. A single-forum plan when the strongest grounds split across two.
[ ] Account for estoppel in the ground selection.
- Authority. 35 U.S.C. § 315(e). A petitioner reaching a final written decision is estopped from asserting grounds raised or that reasonably could have been raised.
- Trap. Holding back a ground to preserve it, and losing it to estoppel anyway.
[ ] File early if a stay matters.
- Why. Stays are discretionary and courts weigh the stage of the litigation. An early petition materially improves the prospects.
[ ] Watch for amendments at the Board.
- Why. A patent owner amending claims in the proceeding changes what is being litigated in court, and may create intervening rights.

Phase 15. Cost and staffing

| Phase | Typical effort | Relative cost | Notes | |---|---|---|---| | Disclaimer table | 10–25 hours | Moderate | Highest return per hour in the exercise | | Specification mapping | 5–10 hours | Low | Delegable with supervision | | Dual-consequence charting | 10–20 hours | Moderate | Must be joint with the invalidity team | | Term selection | 3–8 hours | Low | Senior judgment, not volume | | Local rule compliance | Ongoing | Low | Calendar discipline | | Joint chart | 10–20 hours | Moderate | Support column is the persuasive part | | Construction expert | Weeks | High | Discretionary; skip where the record is clear | | Indefiniteness briefing | 20–40 hours | Moderate | Runs on the construction schedule | | Construction briefing | 40–80 hours | High | The main event | | Tutorial | 15–30 hours | Moderate | Delivered by the arguing lawyer | | Hearing | 1–2 days plus prep | High | | | Post-order motion | Weeks | Moderate | Drafted before the hearing |

[ ] Front-load the analysis phases.
- Why. They cost a fraction of briefing and they determine what the briefing can achieve. A case reaching term exchange without a completed dual-consequence chart has already chosen badly.
[ ] Reserve budget for the post-order motion.
- Trap. Spending the entire construction budget on the hearing, leaving nothing to convert a win into a judgment.
[ ] Set the client's expectation about proportion at the outset.
- Why. A construction phase consuming a large share of the case budget is a sign the case is being litigated where it will be decided. Clients who learn that from invoices resist exactly the work that matters most.

Phase 16. Preserving the appeal

[ ] Propose every construction you may need on appeal.
- Why. Constructions not proposed below are generally unavailable later.
- Authority. 28 U.S.C. § 1295 gives the Federal Circuit exclusive jurisdiction.
[ ] Understand what standard applies to what.
- Why. The ultimate construction is reviewed without deference; subsidiary factual findings from extrinsic evidence are reviewed for clear error. The record chosen at Phase 5 determines which.
[ ] Make the record on materiality.
- Why. The appellate court needs to see that the construction error changed the outcome.
[ ] Consider the stipulated judgment route.
- Why. Where an adverse construction is dispositive, both parties frequently prefer entry of judgment to trying a determined case, and it presents the question cleanly.
[ ] Preserve indefiniteness rulings separately.
- Authority. 35 U.S.C. § 112(b); 35 U.S.C. § 282.
[ ] Keep the disclaimer table and the dual-consequence chart with the appellate file.
- Why. Appellate counsel arriving cold needs both, and reconstructing them costs more than preserving them.

Phase 17. The canon reference

A working reference for the interpretive tools, what each does, and how far it carries.

| Canon | What it says | Weight | Defeated by | |---|---|---|---| | Plain and ordinary meaning | Terms mean what a skilled artisan understood at the time | The default | Lexicography or disavowal | | Claim differentiation | A limitation in a dependent claim is presumed absent from the independent | Strong, rebuttable | A contrary definition or clear disclaimer | | Consistent usage | A term means the same thing throughout the patent and family | Strong | Express contrary definition | | Lexicography | A clear definitional statement controls | Controlling where present | Requires clear intent to define | | Disavowal | A clear and unmistakable surrender limits the claim | Controlling where present | Preference and description are not enough | | Prosecution disclaimer | A clear surrender during prosecution limits the claim | Strong | Ambiguity, or multiple independent grounds | | Preamble | Limiting where it recites essential structure or supplies antecedent basis | Fact-specific | Merely stating purpose or use | | "Comprising" | Open transition; additional elements do not avoid the claim | Settled | Nothing | | "Consisting of" | Closed transition | Settled | Nothing | | "Consisting essentially of" | Permits elements not materially affecting the basic characteristics | Settled | Fact question on materiality | | Validity-preserving construction | Where two constructions are available, one preserving validity has some pull | Weak | Cannot rewrite a clear claim | | Importing embodiments | Not a canon; the error the framework rejects | None | Always | | Dictionary-first | Not a canon; inverts the correct order | None | Always |

[ ] Cite the canon by name in briefing.
- Why. Judges construe claims constantly and recognize the framework. Naming what you are relying on is clearer than arguing around it.
[ ] Do not stack weak canons.
- Trap. Six weak arguments read as an absence of a strong one.
[ ] Check the last two rows against your own brief before filing.
- Why. They are the two most common errors and they are easy to commit without noticing.

Phase 18. Special claim types

[ ] Means-plus-function limitations: identify the function, then the corresponding structure.
- Authority. 35 U.S.C. § 112(f). The construction is the disclosed structure and equivalents, and the absence of structure is indefiniteness under 35 U.S.C. § 112(b).
- Trap. Arguing about the function while ignoring what structure the specification actually discloses.
[ ] Method claims: determine whether the recited order is required.
- Why. A claim listing steps does not necessarily require them in that sequence, and the answer frequently decides infringement.
- Authority. 35 U.S.C. § 271(a). See Proving Patent Infringement.
[ ] Product-by-process claims: construe the product, not the process.
- Trap. Assuming the process limitations narrow the product for infringement purposes.
[ ] Markush groups: determine whether the group is closed.
[ ] Numerical ranges and terms of degree: locate the baseline in the specification.
- Authority. 35 U.S.C. § 112(b).
[ ] Design patent claims: the claim is the drawings.
- Authority. 35 U.S.C. § 171. Construction is generally limited and the comparison is visual. See Three Ways to Own a Shape.
[ ] Claims with a negative limitation: confirm support for the exclusion.
- Authority. 35 U.S.C. § 112(a).

Phase 19. The construction file

What should exist when the matter is handed to trial counsel, appellate counsel, or a successor.

[ ] The disclaimer table.
- Why. Every statement in the family that surrendered scope, with its date, document, and the rejection it answered. It is the most reusable artifact in the file and the most expensive to reconstruct.
[ ] The specification map.
- Why. Each claim term against where it appears, how many embodiments describe it, and whether an algorithm exists for any functional limitation.
[ ] The dual-consequence chart.
- Why. Every construction considered, with its infringement and invalidity consequences. It explains why positions were taken, which appellate counsel needs and which nobody remembers.
[ ] The term selection memorandum.
- Why. Which terms were selected, which were rejected, and why. It is the record of judgment rather than of activity.
[ ] The joint chart and every exchange.
[ ] Expert reports, deposition transcripts, and the level-of-skill definition.
[ ] The tutorial materials.
[ ] The order, annotated for what was decided and what was left at plain meaning.
[ ] The drafted dispositive motion, in both versions.
[ ] Every filing from any parallel proceeding, cross-indexed by claim term.
- Why. The inconsistency risk runs both directions and the cross-index is what prevents it.
- Authority. 35 U.S.C. § 315(e).

A closing note on ownership. Phases 1 through 5 belong to whoever will argue, because they are judgment rather than production and the arguing lawyer needs the record in their head. Phases 6 through 8 are procedural and delegable with supervision. Phases 9 through 12 are the main event. Phase 13 belongs to whoever drafted the motion in advance, which should be the same team. And the file at Phase 19 belongs to whoever inherits the case — which in a patent matter running four years is frequently someone who has not yet been retained.

Phase 20. The client conversation

Clients experience claim construction as a procedural detour before the real event, and the misunderstanding produces bad decisions about budget and settlement.

[ ] Explain at the outset that a patent claim is a written boundary.
- Why. Litigation is a dispute about where the boundary runs before it is a dispute about whether anyone crossed it. Framed that way, the resources devoted to construction stop looking disproportionate.
[ ] Say plainly that most cases are decided here.
- Trap. A client saving the budget for a trial that will not happen, and resisting the expert work and file wrapper review that actually determine the outcome.
[ ] Present the dual-consequence chart, not just the positions.
- Why. It shows the client why the broadest construction is not automatically the best one, which is the point patentee clients find least intuitive.
[ ] Set expectations about the order before the hearing.
- Why. A client who understands that an adverse construction may end the case, and why, absorbs the result differently from one who was told the hearing was preliminary.
[ ] Present the stipulated judgment option in advance.
- Why. It reads as surrender to a client hearing it for the first time after a loss, and as sensible appellate strategy to one who was told about it beforehand.
- Authority. 28 U.S.C. § 1295.
[ ] Update the settlement analysis in writing the week the order issues.
- Why. The construction order is the single largest information event in a patent case, and parties that treat it as a step toward trial spend a great deal confirming what they already learned.

Key Authorities at a Glance

| Authority | Proposition | Phase | |---|---|---| | 35 U.S.C. § 112(a) | Written description and enablement | 3 | | 35 U.S.C. § 112(b) | Definiteness | 2, 9 | | 35 U.S.C. § 112(f) | Means-plus-function construction | 2, 9 | | 35 U.S.C. § 102 | Novelty; the invalidity half of the pincer | 3 | | 35 U.S.C. § 103 | Nonobviousness | 3 | | 35 U.S.C. § 120 | Shared family record | 1 | | 35 U.S.C. § 132(a) | No new matter; the amendment record | 1 | | 35 U.S.C. § 271(a) | Infringement requires every limitation | 3 | | 35 U.S.C. § 282 | Presumption of validity | 9 | | 35 U.S.C. § 284 | Damages | 13 | | 35 U.S.C. § 311(b) | IPR limited to §§ 102 and 103 | 9 | | 35 U.S.C. § 315(e) | Estoppel after a final written decision | 6 | | 35 U.S.C. § 321(c) | Post-grant review window | 9 | | 37 C.F.R. § 1.321 | Terminal disclaimers | 1 | | Fed. R. Civ. P. 26 | Expert disclosures | 8 | | Fed. R. Civ. P. 56 | Summary judgment | 13 | | Fed. R. Evid. 702 | Expert testimony | 8 | | Fed. R. Evid. 703 | Bases of expert opinion | 8 | | 28 U.S.C. § 1295 | Federal Circuit jurisdiction | 13 |

The five things people get wrong

One: they read the specification before the file wrapper. The prosecution history contains the concessions, and concessions are the shortest route to a dispositive construction. It is deferred because it is voluminous, which is exactly why the arguments in it go unfound.

Two: they chart infringement without charting invalidity. Every construction has two consequences, and a patentee arguing for the breadth needed to capture the accused product frequently walks the claim into the prior art. Separate teams for infringement and invalidity make the pincer invisible to both.

Three: they select terms by ambiguity rather than by dispositiveness. The question is not which term is unclear; it is which construction, if adopted, ends the case.

Four: they argue that embodiments limit the claim without invoking lexicography or disavowal. Courts identify it immediately, and it costs credibility on the terms that matter.

Five: they draft the summary judgment motion after the order. The construction order is the case's decisive moment, and the party holding a drafted motion uses it while the other side is still reading. See Litigating Claim Construction.