35 U.S.C. § 119

(a) An application for patent for an invention filed in this country by any person who has, or whose legal representatives or assigns have, previously regularly filed an application for a patent for the same invention in a foreign country which affords similar privileges in the case of applications filed in the United States or to citizens of the United States, or in a WTO member country, shall have the same effect as the same application would have if filed in this country on the date on which the application for patent for the same invention was first filed in such foreign country, if the application in this country is filed within 12 months from the earliest date on which such foreign application was filed. The Director may prescribe regulations, including the requirement for payment of the fee specified in section 41(a)(7), pursuant to which the 12-month period set forth in this subsection may be extended by an additional 2 months if the delay in filing the application in this country within the 12-month period was unintentional. (b) (1) No application for patent shall be entitled to this right of priority unless a claim is filed in the Patent and Trademark Office, identifying the foreign application by specifying the application number on that foreign application, the intellectual property authority or country in or for which the application was filed, and the date of filing the application, at such time during the pendency of the application as required by the Director. (2) The Director may consider the failure of the applicant to file a timely claim for priority as a waiver of any such claim. The Director may establish procedures, including the requirement for payment of the fee specified in section 41(a)(7), to accept an unintentionally delayed claim under this section. (3) The Director may require a certified copy of the original foreign application, specification, and drawings upon which it is based, a translation if not in the English language, and such other information as the Director considers necessary. Any such certification shall be made by the foreign intellectual property authority in which the foreign application was filed and show the date of the application and of the filing of the specification and other papers. (c) In like manner and subject to the same conditions and requirements, the right provided in this section may be based upon a subsequent regularly filed application in the same foreign country instead of the first filed foreign application, provided that any foreign application filed prior to such subsequent application has been withdrawn, abandoned, or otherwise disposed of, without having been laid open to public inspection and without leaving any rights outstanding, and has not served, nor thereafter shall serve, as a basis for claiming a right of priority. (d) Applications for inventors’ certificates filed in a foreign country in which applicants have a right to apply, at their discretion, either for a patent or for an inventor’s certificate shall be treated in this country in the same manner and have the same effect for purpose of the right of priority under this section as applications for patents, subject to the same conditions and requirements of this section as apply to applications for patents, provided such applicants are entitled to the benefits of the Stockholm Revision of the Paris Convention at the time of such filing. (e) (1) An application for patent filed under section 111(a) or section 363 for an invention disclosed in the manner provided by section 112(a) (other than the requirement to disclose the best mode) in a provisional application filed under section 111(b), by an inventor or inventors named in the provisional application, shall have the same effect, as to such invention, as though filed on the date of the provisional application filed under section 111(b), if the application for patent filed under section 111(a) or section 363 is filed not later than 12 months after the date on which the provisional application was filed and if it contains or is amended to contain a specific reference to the provisional application. The Director may prescribe regulations, including the requirement for payment of the fee specified in section 41(a)(7), pursuant to which the 12-month period set forth in this subsection may be extended by an additional 2 months if the delay in filing the application under section 111(a) or section 363 within the 12-month period was unintentional. No application shall be entitled to the benefit of an earlier filed provisional application under this subsection unless an amendment containing the specific reference to the earlier filed provisional application is submitted at such time during the pendency of the application as required by the Director. The Director may consider the failure to submit such an amendment within that time period as a waiver of any benefit under this subsection. The Director may establish procedures, including the payment of the fee specified in section 41(a)(7), to accept an unintentionally delayed submission of an amendment under this subsection. (2) A provisional application filed under section 111(b) may not be relied upon in any proceeding in the Patent and Trademark Office unless the fee set forth in subparagraph (A) or (C) of section 41(a)(1) has been paid. (3) If the day that is 12 months after the filing date of a provisional application falls on a Saturday, Sunday, or Federal holiday within the District of Columbia, the period of pendency of the provisional application shall be extended to the next succeeding secular or business day. For an application for patent filed under section 363 in a Receiving Office other than the Patent and Trademark Office, the 12-month and additional 2-month period set forth in this subsection shall be extended as provided under the treaty and Regulations as defined in section 351. (f) Applications for plant breeder’s rights filed in a WTO member country (or in a foreign UPOV Contracting Party) shall have the same effect for the purpose of the right of priority under subsections (a) through (c) of this section as applications for patents, subject to the same conditions and requirements of this section as apply to applications for patents. (g) As used in this section— (1) the term “WTO member country” has the same meaning as the term is defined in section 104(b)(2); and (2) the term “UPOV Contracting Party” means a member of the International Convention for the Protection of New Varieties of Plants.