Infringement and validity disputes in federal district court, from claim construction through technical case development and damages strategy, with the engineers and economists a patent fight requires.
Patent damages reach back six years from the complaint and no further, and if the patented product was sold without a patent marking they reach back only to the day the infringer was put on notice. We ask for the marking history before we ask for the claim chart.
An infringement claim fails if a single element of the asserted claim is missing from the accused product, literally or by equivalent, so the defense usually begins by finding the element the claim chart glosses over. Venue stopped being the plaintiff's to choose in 2017; a corporate defendant can now be sued only where it is incorporated or where it has a regular and established place of business and has infringed.
Claim construction is a question for the judge, settled at the Markman hearing on the patent's own record, and the ruling usually tells both sides what the case is worth. We build the case for that hearing with the engineers and damages economists whose testimony has to survive it, coordinating with registered patent counsel where the work requires that admission.
Prosecuting and defending patent infringement claims in federal district court, marshalling the technical proof on infringement while developing or rebutting invalidity and unenforceability defenses over the prior art.
Claim-construction strategy and Markman hearing preparation, the contest over how the court reads the claim terms, which more than any other step decides which way a patent case turns.
Coordinating inter partes review and other proceedings before the Patent Trial and Appeal Board, weighing a validity challenge and a possible stay against district-court deadlines and IPR estoppel.
Building the technical record with the engineers, scientists, and testifying experts a patent case depends on, and coordinating with registered patent counsel where the admission requires it.
Damages and royalty strategy, covering lost profits, reasonable-royalty models, enhanced damages for willfulness, and the licensing and settlement analysis that shapes the economics of a case long before trial.
Trial preparation and courtroom advocacy in the district courts, with appeals to the Court of Appeals for the Federal Circuit so a favorable claim construction or verdict can be defended on review.
How the claim terms are read is a question of law decided by the court, not the jury, and the Federal Circuit reviews that reading afresh on appeal, deferring only to findings drawn from expert testimony or other evidence outside the patent. A construction grounded in the specification travels better than one built on experts.
A defendant has one year from service to petition for inter partes review. A court weighs a stay against the stage of the case, the simplification on offer and the prejudice to the patent owner. A final written decision then estops the petitioner from repeating in court any ground it raised or could have raised.
Source code is reviewed on a computer that is never connected to a network, in the producing party's offices, by experts the other side has had a chance to object to. Each side's experts exchange written reports under Rule 26 and are deposed on them; an opinion that first appears at trial is usually excluded.
Drafting and prosecuting applications before the USPTO requires registration as a patent attorney or agent; our work is litigation and strategy, and we coordinate with registered patent counsel where that is required.
Enhanced damages, up to three times the award, are reserved for egregious conduct, and the usual proof is what the defendant knew and when. The statute forbids using the absence of an opinion of counsel to prove willfulness, but a written opinion obtained when the patent first surfaced remains the cleanest answer to the charge.
Lost profits require proof the owner would have made the sales itself: demand, no acceptable substitute, the capacity to supply. Otherwise the measure is a reasonable royalty set in a hypothetical negotiation on the day infringement began, apportioned to the feature the patent covers rather than the price of the whole product.
Before any complaint is filed, the patent is mapped element-by-element against the accused product in claim charts, the prior art is stress-tested, and venue is chosen under the post-TC Heartland rules. A notice letter is weighed carefully, because it can start the willfulness clock and invite a declaratory-judgment strike in someone else's forum.
The case narrows to a handful of disputed claim terms briefed and argued at the Markman hearing, and the ruling often decides infringement and validity in one stroke. In parallel, the defendant must decide before the one-year service bar of 35 U.S.C. § 315(b) whether to petition for inter partes review, seek a stay, and accept the estoppel that follows.
Infringement and invalidity contentions harden into source-code review, engineer depositions, and dueling expert reports, while damages economists build the lost-profits and reasonable-royalty models, apportioned to the smallest salable unit, that will set the number a jury can actually award.
Trial resolves infringement, validity, and damages, with willfulness opening the door to enhancement, and the losing side almost always appeals. Every patent appeal, from every district court, goes to one bench, the Court of Appeals for the Federal Circuit, where the claim construction won below must be defended de novo.
A patent case is decided when the court reads the claims. Everything after Markman is arithmetic.
Patent litigation is the resolution of disputes over patent rights through the courts, most often claims that a product or process infringes an issued patent, together with the accused party's defenses that the patent is invalid or unenforceable. It is decided largely on technical proof and on how the patent's claims are construed, and in the United States it runs through the federal district courts, with appeals to the Court of Appeals for the Federal Circuit.
Hart David Carson LLP's work is litigation and dispute strategy. Drafting and prosecuting patent applications before the USPTO requires registration as a patent attorney or agent, and we coordinate with registered patent counsel for that work where it is required. In a dispute, we manage the case across infringement and validity, claim construction, discovery, damages, and trial, and bring in the technical experts the technology demands.
It turns first on claim construction, meaning how the court reads the words of the patent's claims, usually settled at a Markman hearing. Once the claims are construed, the plaintiff has to show that the accused product or process meets every element of an asserted claim, while the defendant typically argues the patent is invalid over the prior art or unenforceable. Technical expert testimony and the documentary record carry much of the weight on both sides.
Usually alongside, and the decision has a deadline. A defendant has one year from service of the complaint to petition for inter partes review, the petition is limited to prior patents and printed publications, and institution is discretionary, so the Board can decline a strong petition because the district court is close to trial. If the Board institutes, a stay of the court case is likely but not automatic, and the final written decision estops the petitioner from rearguing in court any ground it raised or reasonably could have raised. We decide early which printed prior art goes to the Board and which grounds, prior sales and public use among them, can only be made in court.
Damages are measured by the patent owner's lost profits where they can be proven, or otherwise by a reasonable royalty, meaning what a willing licensor and licensee would have agreed to in a hypothetical negotiation. Enhanced damages are possible for willful infringement, and prevailing parties may seek fees in exceptional cases. We build the damages theory early, because it shapes the economics of settlement long before trial.
It starts with three records: the patent's prosecution history, the owner's marking history and the prior art a search turns up. Those tell us whether damages reach back six years or only to the notice date, which claim elements are open to argument and whether a petition to the Board is worth the estoppel it carries. From there we price the exposure, pick the forum the venue statute allows and decide whether a license costs less than the fight. That arithmetic, not a year of discovery, decides whether the case is tried or settled.
Patent litigation under the Hatch-Waxman framework, the ANDA disputes between branded and generic pharmaceutical companies over patent validity and infringement.
Explore →Section 337 investigations before the U.S. International Trade Commission, seeking exclusion-order relief against infringing imports on the Commission's fast-moving schedule.
Explore →Inter partes review and other Patent Trial and Appeal Board proceedings that challenge or defend patent validity on the PTAB's faster, lower-cost track.
Explore →Enforcement and defense of trademark and copyright rights in the infringement, dilution, and ownership disputes over the brands and creative works that carry value.
Explore →Reviewed by Jonathan D. Herpy, Sr., Senior Partner · Last updated October 2026 · Educational overview · Not legal advice
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