For a patentee filing for patent protection regarding an invention made in the United States, a license is required before filing any application for a patent in a foreign country. Failure to get a foreign filing license can lead to invalidation of subsequently granted patents (35 U.S.C. §185), and a fine of up to $10,000 or imprisonment for up to two years, or both, if the patentee is convicted of willfully disclosing subject matter subject to a Secrecy Order, (35 U.S.C. §186). Invalidation of a patent under 35 U.S.C. § 185 only occurs if the failure to do so was not through error and the invention concerns national security. See, Genes Indus. v. Custom Blinds & Components, 2016 U.S. Dist. LEXIS 203623, at *17 (C.D. Cal. Sept. 26, 2016). For more discussion on obtaining a foreign filing license prior to filing an application for a foreign patent, see

But what if the foreign patent application was already filed? Obtaining a retroactive foreign filing license is possible, though it may take time and several petitions. Under 35 U.S.C. § 184, the statute authorizes granting a foreign filing license retroactively “where an application has been filed abroad through error and the application does not disclose an invention within the scope of section 181.” Section 181 requires disclosures considered important to national security be kept secret or at least be available for inspection by government agency heads.

The petition for a retroactive foreign filing license should be used only if an unlicensed foreign filing occurred through error and is very limited in scope (only the necessary specific filings in the necessary foreign countries). Thus, for each act, the patentee must provide the USPTO with the countries, the actual dates of filing, the nature of the error, and a verified statement in the form of either an oath or declaration. Under 37 C.F.R. § 5.25, it sets out the requirements, inter alia, that the verified statement include:

  • An averment that the subject matter in question was not under a secrecy order at the time it was filed aboard [sic], and that it is not currently under a secrecy order,
  • A showing that the license has been diligently sought after discovery of the proscribed foreign filing, [and]
  • An explanation of why the material was filed abroad through error without the required license under § 5.11 first having been obtained.

Rule 5.25 further requires that the “showing of facts as to the nature of the error should include statements by those persons having personal knowledge of the acts regarding filing in a foreign country” and “should cover the period leading up to and including each of the proscribed foreign filings.”

If the petition is denied, the U.S. applicant has 30 days to renew the petition. If there is no renewal, the denial is considered final. The applicant then has two months to file a petition under § 1.181, otherwise a final rejection of the application under 35 U.S.C. § 185 will be made. See also, M.P.E.P. § 140 Foreign Filing Licenses [R-07.2022] and

If granted, the license is retroactive with respect to the specific instance of foreign filing. The license, when granted, “assumes its required position ahead of the foreign filing in the order of procedure.” 3M v. Norton Co., 366 F.2d 238, 241 (6th Ct. App. Sept. 19, 1966). In addition, if granted, the license covers all “modifications, amendments, and supplements” which do not change the “general nature of the invention” so as to require inspection under 35 U.S.C. §181.