Guide, September 2026
US Patent Attorney for Foreign Applicants: the 2026 Representation Rule
Since July 20, 2026 a foreign-domiciled applicant or patent owner has to be represented by a registered US patent practitioner. Here is what changed, who it covers, and what a foreign associate actually needs from US counsel.
What changed
The USPTO amended the rules of practice in patent cases to require applicants, inventors, and patent owners domiciled outside the United States and its territories to be represented by a registered patent practitioner. The final rule was published at 91 Fed. Reg. 13510 on March 20, 2026 and took effect on July 20, 2026. It amends 37 CFR 1.9, 1.31, 1.32, and 1.33.
The trademark side of the office has had an equivalent requirement since 2019. The patent side has now caught up. The office framed the change as bringing US practice in line with most other patent offices and as making compliance easier to enforce.
Who it covers
Domicile decides it, not nationality. The USPTO normally reads an inventor-applicant's domicile from the residence given in the application data sheet or in the inventor's oath or declaration, and a non-inventor applicant's domicile from the mailing address in the Applicant Information section. The requirement now reaches patent owners as well, so an assignment to a foreign entity brings the case inside the rule.
What a foreign firm needs from a US practitioner
- A registered practitioner's signature on covered papers. A paper that needs one and lacks it is not entered.
- A US correspondence address of record, so office mail reaches someone who will docket it and act.
- A power of attorney on file, so the practitioner can prosecute rather than forward paper.
- An agreed split of drafting and signing work, settled before the first response is due rather than in the last week of a three-month clock.
How we work with foreign associates
We act as US counsel for foreign firms and corporations entering the US system. The work is USPTO procedure, the gap between a home-country patent system and US practice, technical translation and terminology, and communication with the examiner. See Foreign Firms & Corporations for how that engagement is structured.
Regional notes
Japan. Japanese applicants usually come through a benrishi firm that already coordinates US filings, so the change is mostly administrative. Confirm the power of attorney and the correspondence address of record name the US practitioner rather than the Japanese firm.
Korea. Korean applicants often file a US provisional or a Paris Convention application directly to hold a date. That direct route is where the rule bites, because a registered US practitioner has to sign the covered papers even when the Korean firm drafted them.
Europe. European attorneys are used to a representation requirement, since the EPO has one. The mechanics differ. A European patent attorney is not a registered US patent practitioner, so EPO representation does not carry over to the USPTO.
China. Chinese applicants file a large volume of US cases, including many from individual inventors and small entities that previously self-represented. Those are the filings most likely to hit an unentered paper after July 20, 2026.
Sources
Common questions
Do foreign applicants need a US patent attorney at the USPTO?
Yes, for papers received on or after July 20, 2026. The USPTO's final rule requires patent applicants, inventors, and patent owners whose domicile is not in the United States or its territories to be represented by a registered US patent practitioner. The rule is published at 91 Fed. Reg. 13510 (March 20, 2026).
When did the USPTO foreign applicant representation requirement take effect?
The final rule was published on March 20, 2026 and is effective July 20, 2026. It reaches covered papers received on or after that date, including new applications, amendments, and replies, regardless of when the underlying application was filed.
Does the representation rule apply to applications filed before July 20, 2026?
It attaches to the papers, not to the filing date of the case. A pending application filed years earlier still needs a registered practitioner to sign covered papers received on or after the effective date. A foreign applicant handling a pending case alone needs US representation in place before the next response is due.
Who counts as a foreign-domiciled applicant at the USPTO?
Domicile is read from the record, not from nationality. For an inventor-applicant the USPTO normally looks at the residence in the application data sheet under 37 CFR 1.76 or in the inventor's oath or declaration under 37 CFR 1.63. For a non-inventor applicant it normally looks at the mailing address in the Applicant Information section of the ADS.
Does the representation rule cover patent owners as well as applicants?
Yes. It reaches foreign-domiciled patent owners, and the juristic-entity representation requirement was expanded from applicants to patent owners. That matters after an assignment and in post-issuance matters.
What does a foreign law firm need from a US patent practitioner?
Three things in practice. A registered practitioner's signature on covered papers. A US correspondence address of record, so USPTO mail reaches someone who will docket it. And a power of attorney on file, so the practitioner can prosecute the case rather than forward paper.
What happens to a paper filed without a registered practitioner signature?
A paper that requires a practitioner signature and lacks one is not entered into the record. Amendments, application data sheets, and information disclosure statements are the usual casualties. The unentered IDS is the dangerous one, because the applicant may believe a disclosure obligation was met when it was not.
This guide is general information about USPTO procedure, not legal advice for any particular case. For fees, see the patent prosecution cost guide.