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The One Year You Get, and What It Does Not Cover

Written from 35 U.S.C. 102(b). This is the statute. Current as of 22 August 2026.

What it says

A disclosure made one year or less before the effective filing date is not prior art under section 102(a)(1) if either of two exceptions applies. One turns on the disclosure originating with an inventor. The other turns on an inventor having publicly disclosed the same subject matter first.

The grace period is real and it is narrower than its reputation.

The statute excepts a disclosure made one year or less before the effective filing date if either of two conditions holds. The first is that the disclosure was made by an inventor or joint inventor, or by another who obtained the subject matter directly or indirectly from them. The second is that the subject matter had already been publicly disclosed by an inventor, or by someone who obtained it from them.

The two routes work differently, and conflating them is the common error.

(b)(1)(A) is about origin. It reaches a disclosure made by an inventor, or by someone who got the subject matter from an inventor. A person who arrived independently is outside it.

(b)(1)(B) is about sequence. It reaches a disclosure where the subject matter "had, before such disclosure, been publicly disclosed by the inventor or a joint inventor." The later discloser needs no connection to the inventor at all. What matters is that an inventor publicly disclosed the same subject matter first.

So the accurate statement is narrower than it first looks. The statute gives no grace period against a third-party disclosure that comes first. But a third-party disclosure that follows an inventor's own public disclosure of the same subject matter may be removed under (b)(1)(B).

Two limits on that. It reaches only the subject matter the inventor actually disclosed, so anything additional or materially different in the later disclosure is untouched. And it depends on the inventor's earlier disclosure having been public.

It is also a United States provision. Other jurisdictions handle pre-filing disclosure differently, and several are considerably less forgiving.

What This Does Not Decide

This is not a reason to wait, and it is not cover against anyone else. A page describing a grace period invites both readings, and the statute supports neither. What the exception does is described above; whether it reaches a particular disclosure, and what a delay would cost elsewhere, are questions for a practitioner.
  • It does not say whether any disclosure of yours falls inside the exception.
  • It offers no protection against a third-party disclosure that came first. Whether a later one is removed under (b)(1)(B) turns on what an inventor disclosed publicly, and when, compared against what the third party disclosed.
  • It says nothing about foreign filing, where pre-filing disclosure is often treated far more strictly.
  • It is not advice about when to file.

Educational, not legal advice. Whether any of this reaches a particular disclosure is a determination for a registered patent practitioner working from the actual facts and dates.

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