Grace period

WIPO notes that the novelty criteria may be interpreted differently depending on the applicable law¹. The table compares the four systems this page covers. It is a summary: each system has conditions that the sections below set out. Other jurisdictions are not covered here.

A grace period is not the same as a priority period. The Paris Convention priority period protects a later filing against acts accomplished in the interval after the first filing (Article 4B)⁷. A grace period concerns disclosures made before filing. See Priority date and Paris Convention.

A disclosure made 1 year or less before the effective filing date of a claimed invention is not prior art under section 102(a)(1) if one of two conditions is met².

• Section 102(b)(1)(A). The disclosure was made by the inventor or a joint inventor, or by another who obtained the subject matter disclosed directly or indirectly from the inventor or a joint inventor².
• Section 102(b)(1)(B). The subject matter disclosed had, before such disclosure, been publicly disclosed by the inventor or a joint inventor, or by another who obtained it directly or indirectly from them². The USPTO says the subject matter in the third-party disclosure relied on as prior art must be the same subject matter the inventor had publicly disclosed, and that the exception does not apply even if the only differences are mere insubstantial changes, or only trivial or obvious variations¹¹.

Section 102(b)(2) provides separate exceptions for disclosures that are prior art only under section 102(a)(2), that is, US patents, published US applications and applications deemed published under section 122(b), and it is not limited to one year². The MPEP section on these exceptions applies only to applications examined under the first inventor to file provisions of the AIA, and it points to MPEP 2155.02 and 2155.03 on using affidavits or declarations to show the facts that bring a disclosure within the exceptions¹¹.

The one year counts back from the effective filing date, which can be the filing date of an earlier application whose right of priority or benefit the application claims (35 U.S.C. 100(i))⁸.

For the application of Article 54 EPC, a disclosure of the invention is not taken into consideration if it occurred no earlier than six months preceding the filing of the European patent application and was due to, or in consequence of, one of two things. The first is an evident abuse in relation to the applicant or the applicant's legal predecessor. The second is the display of the invention by them at an official, or officially recognized, international exhibition within the terms of the 1928 Paris Convention on international exhibitions, last revised in 1972 (Article 55(1))³.

The EPO Guidelines state that there are only two specific cases in which a prior disclosure of the invention is not taken into consideration as part of the state of the art⁴. The EPC therefore has no general grace period for an applicant's own disclosures.

• Time limit. The six months run from the actual date of filing of the European application, not the priority date (decisions G 3/98 and G 2/99)⁹.
• Evident abuse. The Guidelines say the disclosure may be made in a published document or in any other way. For evident abuse to be established, the person disclosing must have had either actual intent to cause harm or actual or constructive knowledge that harm would or could ensue, proven on the balance of probabilities⁶.
• Exhibitions. The applicant must state, when filing, that the invention has been so displayed, and must file a supporting certificate within the time limit under the Implementing Regulations (Article 55(2))³. The Guidelines say the certificate must be filed within four months, and that the recognized exhibitions are published in the Official Journal¹².

• WIPO advises that if disclosure before filing is unavoidable, for example to a potential investor or business partner, the disclosure should be accompanied by a confidentiality or non-disclosure agreement¹.
• Check each country where you plan to file. The JPO warns that publishing before filing can prevent a patent abroad⁵, and the EPC excuses only the two cases in Article 55^3,4. In the US, only disclosures made 1 year or less before the effective filing date can qualify under section 102(b)(1)^2,8.
• Keep the formal steps in mind: a statement and supporting certificate for the EPC exhibition case³, a declaration and proof within two months for the China exhibition and conference cases¹³, and, for an applicant's own disclosure in Japan, a statement at filing and proof within 30 days⁵.