This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.
The USPTO allows for partial disqualification of prior art through a 37 CFR 1.130(b) declaration. If the declaration shows that only a portion of the intervening disclosure was previously publicly disclosed by the inventor, the remaining portion may still be available as prior art. The MPEP states:
Any remaining portion of an intervening grace period disclosure that was not previously publicly disclosed by the inventor or a joint inventor or another who obtained the subject matter disclosed directly or indirectly from the inventor or a joint inventor is available as prior art under 35 U.S.C. 102(a)(1).
For example: If the inventor or a joint inventor had publicly disclosed elements A, B, and C, and a subsequent intervening grace period disclosure discloses elements A, B, C, and D, then only element D of the intervening grace period disclosure is available as prior art under 35 U.S.C. 102(a)(1).