---
kind: "section"
citation: "37 C.F.R. § 1.491"
title: "37"
number: "1.491"
heading: "National stage commencement, entry, and fulfillment."
url: "https://uscodex.org/cfr/37/1.491"
---

# §1.491. National stage commencement, entry, and fulfillment.

- (a) Subject to [35 U.S.C. 371(f)](/usc/35/371.md?p=f), the national stage shall commence with the expiration of the applicable time limit under PCT Article 22 (1) or (2), or under PCT Article 39(1)(a).
- (b) An international application enters the national stage when the applicant has filed the documents and fees required by 35 U.S.C. [371(c)(1)](/usc/35/371.md?p=c-1) and [(c)(2)](/usc/35/371.md?p=c-2) within the period set in [§ 1.495](/cfr/37/1.495.md).
- (c) An international application fulfills the requirements of [35 U.S.C. 371](/usc/35/371.md) when the national stage has commenced under 35 U.S.C. [371(b)](/usc/35/371.md?p=b) or [(f)](/usc/35/371.md?p=f) and all applicable requirements of [35 U.S.C. 371](/usc/35/371.md) have been satisfied.

## Notes

### Amendments

[67 FR 523, Jan. 4, 2002, as amended at 77 FR 48823, Aug. 14, 2012]

### Authority

Authority: Secs. 1.401 to 1.499 also issued under 35 U.S.C. 41 and 351 through 376.

### Source

Source: 43 FR 20466, May 11, 1978, unless otherwise noted.

### Authority

Authority: 35 U.S.C. 2(b)(2), unless otherwise noted.

### Source

Source: 24 FR 10332, Dec. 22, 1959, unless otherwise noted.

### Amendments

[67 FR 523, Jan. 4, 2002, as amended at 77 FR 48823, Aug. 14, 2012]