Patent Local Rules: Contentions, Markman, and Deadlines

Patent local rules are procedural requirements that federal district courts impose on patent cases, forcing both sides to disclose their technical theories early, exchange proposed meanings for disputed claim terms on a court-set schedule, and follow strict protocols for confidential information and attorney advice. More than 30 federal districts have adopted some version of them, and if your case is filed in or transferred to one of those districts, compliance is mandatory. The practical effect is that a patent lawsuit under these rules looks nothing like an ordinary civil case: positions lock in within weeks of filing, and theories left out of early disclosures usually cannot be raised later.

Where These Rules Come From and When They Apply

Federal Rule of Civil Procedure 83 lets each federal district court adopt its own local rules, provided they do not conflict with federal statutes or the Federal Rules of Civil Procedure.¹ Patent local rules are an exercise of that authority, built around the unusual procedural demands of patent litigation. They operate as a procedural overlay on top of the ordinary civil rules.

Many districts base their rules on the Federal Circuit Bar Association’s Model Patent Local Rules, though each court can modify the model.² Individual judges sometimes layer on chambers-specific requirements on top of the district’s rules, so checking both the district rules and the assigned judge’s standing orders is part of the initial case workup.

The rules generally reach any civil case alleging patent infringement, any case seeking a declaratory judgment that a patent is invalid or unenforceable, and any case raising patent-related counterclaims.³ Parties cannot opt out by agreement.

Infringement Contentions: What the Patent Holder Must Disclose

The party alleging infringement serves a “Disclosure of Asserted Claims and Infringement Contentions,” typically within 14 days after the initial case management conference.³ This is not a general accusation. The patent holder must produce a claim chart mapping every element of every asserted claim to the specific feature or component of the accused product or process that supposedly infringes.² Each accused product must be identified by name or model number when that information is known.

For every claim limitation, the disclosure must state whether infringement is alleged literally or under the doctrine of equivalents, which treats a product as infringing when it performs substantially the same function in substantially the same way to achieve substantially the same result, even without matching each claim element exactly.³ A willfulness allegation requires its own factual basis in the disclosure. The patent holder also has to identify the priority date for each asserted claim, the point of first infringement, and the start and end dates of claimed damages.

Mandatory document production rides along with the contentions. The patent holder produces documents showing conception and development of the invention, the complete patent file history, proof of ownership, and any documents reflecting prior disclosures or sales that predate the application.²

Invalidity Contentions: What the Accused Infringer Must Disclose

The accused infringer responds with “Invalidity Contentions,” typically 45 days after receiving the infringement contentions.² These identify each piece of prior art said to anticipate or render obvious each asserted claim. Prior art can include earlier patents, published articles, products that were publicly sold or used, and other evidence that the claimed invention was not actually new when the application was filed.³

Each reference has to be charted against the claims element by element, the mirror image of the patent holder’s infringement chart. If obviousness is based on a combination of references, the specific combination and the reason a person skilled in the field would have combined them has to be laid out. Vague gestures at the general state of the art will not satisfy the rules.

The accused infringer’s document production obligations include source code, specifications, schematics, or other technical documentation sufficient to show how the accused product works, plus copies of all prior art references not already in the patent’s file history.²

Amending Contentions Requires Good Cause

Early disclosure would mean little if parties could freely rewrite their theories later. Changing either side’s contentions requires court permission, and the standard is deliberately demanding.

A party seeking to amend has to show “good cause,” and the analysis turns on diligence. The rules identify three situations that typically support good cause: the court adopted a claim construction different from what the party proposed, the party recently discovered material prior art despite an earlier diligent search, or the party recently discovered nonpublic information about the accused product that was not available despite diligent efforts before contentions were served.³ Finding new information is not enough on its own. You have to show you could not have found it earlier and that you moved quickly once you did.²

The rules also make clear that the general duty to supplement discovery responses under the Federal Rules of Civil Procedure does not substitute for court approval to amend contentions. Quietly updating positions as the case develops is not permitted.

What Happens If You Miss a Disclosure

Courts enforce patent local rules firmly, and preclusion is the standard sanction. A theory left out of your contentions generally cannot be raised later. Courts have barred parties from asserting entire patents they failed to chart, struck doctrine-of-equivalents theories that were not adequately disclosed, and granted summary judgment on invalidity defenses that an accused infringer failed to include in its contentions.

Expert reports draw the same scrutiny. If an expert’s analysis adds theories or claim mappings that were not in the contentions, courts will strike the report or disregard it at summary judgment. This is where many litigants stumble. The expert report is not the place to flesh out a technical case for the first time; the contentions set the outer limits, and the expert has to work inside them. Treating the contentions as a rough draft is one of the fastest ways to lose a patent case on procedural grounds.

Claim Construction and the Markman Hearing

After contentions, the case moves to claim construction, the process of defining disputed terms in the patent claims. The meaning assigned to a single word can determine whether a product infringes and whether a claim is valid, so this phase carries disproportionate weight.

Each party identifies the terms it believes the court needs to interpret. The parties then exchange preliminary claim constructions that include each side’s proposed definition for every disputed term, the portions of the patent specification and prosecution history supporting each definition, and any extrinsic evidence such as dictionary definitions, technical treatises, or expert testimony the party intends to use.⁴ Extrinsic evidence not identified at this stage is likely to be excluded later.²

The parties then file a Joint Claim Construction and Prehearing Statement listing the terms they agree on, the disputed terms, and the evidence each side will present.⁴ Claim construction discovery, including depositions of any identified witnesses, generally has to be completed within 28 days of that filing.²

The process culminates in a Markman hearing, named for the Supreme Court’s 1996 decision holding that “the construction of a patent, including terms of art within its claim, is exclusively within the province of the court.”⁵ The judge decides claim meaning as a matter of law. The jury later applies those definitions to decide infringement. The court’s claim construction order then governs the rest of the case: expert opinions are built around it, and jury instructions incorporate it.

Claim construction is also the forum for challenging whether a claim is indefinite and therefore invalid. Under Nautilus v. Biosig Instruments, a claim is indefinite if it fails “to inform, with reasonable certainty, those skilled in the art about the scope of the invention.”⁶ A patent holder who leans heavily on extrinsic evidence to defend a broad construction can inadvertently invite that challenge, because a claim that needs that much outside support may lack the required certainty.

Protective Orders, AEO, and the Prosecution Bar

Patent cases routinely involve trade secrets, proprietary source code, and competitively sensitive business data. Patent local rules address this with protective-order frameworks that govern how confidential material is handled.

Some districts provide a default protective order that applies automatically unless the parties agree on something different. The Northern District of California, for example, has a model protective order built for patent cases involving highly sensitive information and trade secrets, which takes effect under the court’s patent local rules unless the parties obtain a different order.⁷

The most restrictive tier of confidentiality is typically “Attorneys’ Eyes Only.” It limits access to outside counsel, their staff, litigation support contractors, and the court. The party’s own employees and executives cannot see AEO material, even though they may be running the business whose fate hinges on the case.⁸ The designation applies to information a party contends is a trade secret or proprietary data that the owner has taken reasonable measures to keep confidential.

Patent protective orders also typically include a prosecution bar. An attorney who reviews the opposing side’s confidential technical information cannot later prosecute patent applications on related subject matter. The concern is practical: an attorney who sees a competitor’s confidential source code or product roadmap should not be drafting claims shaped by that knowledge. The bar is personal to the attorney who reviewed the material, not imputed to the whole firm, and it typically runs until one year after the case concludes, including any appeals.⁸ “Prosecution” for these purposes covers drafting or amending claims, advising on post-grant review proceedings, and counseling clients on strategies for obtaining patent rights before the USPTO. Attorneys subject to the bar can still discuss the general status of the case and settlement offers with their clients; they just cannot share the confidential material itself or use it to steer prosecution decisions.

Advice of Counsel: A Deadline That Can Cost You the Defense

A party that plans to rely on advice from its attorneys, particularly against willful infringement allegations, faces specific disclosure requirements tied to the claim construction timeline. Under the Northern District of California’s rules, a party relying on an advice-of-counsel defense must produce all written advice and related documents for which privilege has been waived, provide a written summary of any oral advice, and serve a privilege log identifying any related documents being withheld. The deadline is 30 days after the court’s claim construction ruling.³

Enforcement is blunt. A party that fails to comply cannot rely on advice of counsel for any purpose unless every other party agrees or the court orders otherwise. Since the defense can be decisive on willfulness and the enhanced damages that follow, the stakes of missing this deadline can run into seven or eight figures.

How Discovery Gets Sequenced Differently

Patent local rules reshape the timeline in ways that depart from ordinary civil cases. Rather than one open discovery period, the rules impose a sequence where each phase builds on the one before it.

Claim construction discovery usually closes before broader fact discovery on damages and willfulness opens. The reasoning is that a Markman ruling can reshape or eliminate theories entirely, so spending heavily on damages expert depositions before claim construction wastes resources on theories that may not survive. Courts keep discretion to adjust based on the number of patents, the complexity of the technology, and the number of parties.⁹

Experts follow their own sequence. Claim construction experts have to be identified during the preliminary exchange, with their expected testimony summarized so the other side knows what to prepare for.² Their depositions have to be completed inside the claim construction discovery window. Liability and damages experts come later, after the court has ruled on claim construction and the parties know which theories remain.

Dispositive motions are affected too. When a claim construction issue could resolve the case, some courts allow or require summary judgment to be filed alongside claim construction briefing rather than after expert discovery closes.¹⁰ That can end a case months or years sooner. For other dispositive motions, the deadline typically falls after expert discovery, giving the parties a full evidentiary record before asking the court to rule as a matter of law.

1
Cornell Law Institute. Federal Rules of Civil Procedure Rule 83 – Rules by District Courts; Judge’s Directives
2
Federal Circuit Bar Association. Federal Circuit Bar Association Model Patent Local Rules
3
United States District Court Northern District of California. Patent Local Rules
4
United States District Court Eastern District of Washington. Local Patent Rules
5
Justia Law. Markman v. Westview Instruments, Inc., 517 US 370 (1996)
6
Justia Law. Nautilus, Inc. v. Biosig Instruments, Inc., 572 US 898 (2014)
7
United States District Court Northern District of California. Model Protective Orders
8
United States Court of Federal Claims. Protective Order in Patent Cases
9
United States District Court. Patent Rules – Eastern District of Texas
10
United States District Court District of Utah. Local Rules of Patent Practice