IP Law Essentials

Patent Local Rules: Knowing Them Well Can Make Litigating Your Case Smoother


Federal district courts throughout the country have enacted "patent local rules" that streamline how patent cases are litigated. Here we provide a brief description of what they are, how they are applied, and some reasons why you need to know them intimately.

Q1. What are patent local rules?

Patent local rules ("PLRs") are specialized procedural rules for patent infringement cases. For example, the United States District Court for the Northern District of California instructs that its PLRs "apply to all civil actions filed in or transferred to this Court which allege infringement of a utility patent in a complaint, counterclaim, cross-claim or third party claim, or which seek a declaratory judgment that a utility patent is not infringed, is invalid or is unenforceable." N.D. Cal, Patent L.R. 1-2. PLRs will often also apply to design patent cases. Patent local rules supplement and may sometimes modify the Federal Rules of Civil Procedure and/or the civil local rules of a district court. They also often codify case law requirements for patent cases, e.g., establishing claim construction timing and procedures. The Federal Circuit has consistently upheld PLRs as a proper exercise of the trial court's case-management discretion, characterizing the rules as "seek[ing] to balance the right to develop new information in discovery with the need for certainty as to the legal theories." See O2 Micro Int'l Ltd. v. Monolithic Power Sys., Inc., 467 F.3d 1355, 1366 (Fed. Cir. 2006).

Q2. How do districts and/or courts implement PLRs?

Like civil local rules, districts can implement PLRs on a district-wide basis. For example, the Northern District of California was the first district to adopt PLRs in 2000, and N.D. Cal. courts use those PLRs throughout that district. Some judges also adopt their own chambers rules or implement standing orders that modify their district's PLRs. Generally, the schedule set forth in the PLRs (as modified by the court or the parties' agreement, if applicable) becomes part of the scheduling order in a patent infringement case. Parties litigating in districts or in front of judges without PLRs may want to consider stipulating to the use of PLRs from another district in an effort to streamline litigation.

Q3. What do PLRs generally include?

The Federal Circuit describes PLRs as "essentially a series of case management orders." See O2 Micro Int'l Ltd., 467 F.3d at 1363. PLRs generally include deadlines and requirements relating to patent disclosures and claim construction proceedings events unique to patent litigation that may be case-dispositive. Examples of PLRs include setting deadlines for the disclosure of asserted claims and accused products, the early exchange of the parties' infringement and non-infringement contentions, invalidity and response to invalidity contentions, and damages contentions. Other rules set presumptive limits on the number of claim terms to be construed and set deadlines for opening, responsive, and reply claim construction briefs. Failure to follow these rules can cause an untimely disclosure of an infringement theory or defense to be dismissed/excluded from the case.

Q4. Why would I want PLRs?

First, PLRs tend to make the timing of patent cases more predictable, which generally improves overall management of cases for the court and the litigants. Second, discovering an opponent's theory of liability or defenses may be difficult to achieve through traditional discovery mechanisms, like contention interrogatories. And even if achievable, parties may solidify infringement and/or invalidity theories late in litigation when further discovery is unavailable, effectively prejudicing the propounding party. PLRs are designed to foreclose on an opponent's delay in disclosure or amendment to its theories, and expedite resolution of disputes related to those disclosures. By both parties understanding the metes and bounds of the claims and defenses, it focuses discovery, claim construction disputes, and ideally helps expedite a less costly resolution of the case.

Q5. Which jurisdictions that hear the most patent cases have PLRs?

The table below shows the jurisdictions that preside over the most patent cases in the United States, along with whether some form of PLRs are available in the jurisdiction. As you can see, only two jurisdictions do not have district-wide PLRs.

Jurisdiction (2019 cases)[1]


District of Delaware (1001)


Central District of California (346)


Eastern District of Texas (333)


Western District of Texas (279)[4]


Northern District of California (240)


District of New Jersey (145)


Northern District of Illinois (143)


Southern District of New York (106)



[1] Jacqueline Bell, "A Decade of Patent Litigation in 4 Charts," Law360, https://www.law360.com/articles/1248307 (last visited April 10, 2020).

[2] Delaware's Default Standard for Discovery requires infringement and validity contentions along with specialized document production on par with more formal PLRs.

[3] Although the Central District of California has not yet adopted formalized PLRs, Judges Guilford, Staton, and Wright do have standing orders with PLRs for patent cases.

[4] The Western District of Texas is emerging as one of the leading jurisdictions for patent cases filed in 2020, and its caseload is on par with the District of Delaware. For example, between January 1 and April 27, 2020, the following jurisdictions have seen the most patent cases filed: D. Del. (232), W.D. Tex. (225), E.D. Tex. (120), C.D. Cal. (108), D.N.J. (72), N.D. Ill. (69), N.D. Cal. (65), and S.D.N.Y. (27). (Source: Lex Machina)

[5] Judge Albright in the Waco Division has a standing order governing proceedings in patent cases that do require the core PLR disclosures.

More questions? Contact the authors or visit Fish’s Intellectual Property Law Essentials.