35 U.S.C. § 119 — Benefit of earlier filing date; right of priority

(a) If a person (or their legal representative or assignee) first files a patent application for an invention in a foreign country, and later files for the same invention in the United States, the U.S. application gets treated as if it were filed on that earlier foreign filing date. This only works if the foreign country gives the same right to U.S. applicants or citizens, or is a WTO member country, and if the U.S. application is filed within 12 months of the foreign filing. The Director may allow this 12-month window to be extended by 2 more months, if a fee is paid and the delay in filing was unintentional. (b) (1) To get this right of priority, the applicant must file a claim identifying the foreign application's number, the country or authority it was filed in, and its filing date, within whatever time the Director requires during the application's pendency. (2) If the applicant misses that deadline, the Director may treat it as giving up the priority claim — but the Director may also set up a process, requiring a fee, to accept a claim that was unintentionally filed late. (3) The Director may also require a certified copy of the original foreign application, its specification and drawings, a translation if it isn't in English, and other information, all certified by the foreign patent authority and showing the filing dates involved. (c) The same priority right can instead be based on a later foreign application in the same country, rather than the first one filed — but only if the earlier foreign application was withdrawn, abandoned, or otherwise dropped before being made public, without leaving any rights outstanding, and was never used (before or since) as the basis for a priority claim. (d) If a foreign country lets applicants choose between filing for a patent or for an "inventor's certificate," an application for an inventor's certificate gets the same priority treatment as a patent application, under the same conditions — but only if the applicant qualifies for the benefits of the Stockholm Revision of the Paris Convention at the time of filing. (e) (1) A U.S. nonprovisional application (filed under section 111(a) or as an international application under section 363) gets the filing date of an earlier U.S. provisional application for the same invention, as long as the invention was properly disclosed in that provisional application, the inventors match, the nonprovisional is filed within 12 months of the provisional, and it contains (or is amended to contain) a specific reference to the provisional. As with foreign priority, the Director may allow a 2-month extension for unintentional delay, with a fee, and may accept a late-added reference to the provisional application if the delay in adding it was unintentional — otherwise, missing the deadline can mean losing this benefit. (2) A provisional application can't be relied on in any Patent and Trademark Office proceeding unless its filing fee has been paid. (3) If the 12-month deadline for a provisional application falls on a Saturday, Sunday, or D.C. federal holiday, it's pushed to the next business day. For international applications filed under section 363 somewhere other than the U.S. Patent and Trademark Office, the 12-month and 2-month periods are instead extended as the applicable treaty and its regulations provide. (f) Applications for plant breeder's rights filed in a WTO member country, or in a foreign country party to the UPOV Convention, get the same priority treatment described in subsections (a) through (c) as patent applications, under the same conditions. (g) Definitions: "WTO member country" has the meaning given in section 104(b)(2). "UPOV Contracting Party" means a member of the International Convention for the Protection of New Varieties of Plants.