Many patent owners are interested in trying to draft a single patent application that will serve them in several countries. This is ambitious, since there are many differences between various countries' patent systems, but perhaps not impossible. The patent drafter just needs to be aware of and try to balance all the different requirements in the single patent application. This series of articles will outline some important considerations when drafting a single patent application.

In this first article, we will review the grace period provisions in the U.S., Korea, China, and the European Patent Office (“EPO”). It is a requirement in all jurisdictions that a patent may only be granted if an invention is new (i.e. is not disclosed in the prior art before the filing date or, if priority is claimed, before the priority date). Certain countries, however, allow “grace periods” for inventor disclosures, meaning that such disclosures do not form part of the prior art. Grace periods can be particularly valuable for pharmaceutical inventions if, for example, clinical trial data is required to support the claims., but the clinical trial protocol is published before the filing or priority date (whichever is applicable). At least in the United States, as seen in Sanofi v. Watson and Vanda v. Westward, mere publication of a protocol does not trump later patent claims directed to the results of the protocol.  

United States

In the U.S., under the AIA, the available grace period is one-year prior to the effective filing date and applies in two situations:

  1. Under 35 U.S.C. § 102(b)(1)(A), it applies when the disclosure was made by the inventor or joint inventor or by another who obtained the subject matter disclosed directly or indirectly front the inventor or a joint inventor.
  2. Under 35 U.S.C. § 102(b)(1)(B), it applies when the subject matter disclosed had, before such disclosure, been 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.

Thus, according to AIA § 102(b)(1)(B), if an inventor publicly discloses his or her invention prior to filing, the inventor's disclosure “antedates” a third party's disclosure of the invention made in the interim.

The application of this provision, however, may be limited to the “same invention” (and may not encompass obvious variants) although the U.S. case law has not made this clear. In particular, the United States Patent and Trademark Office (“USPTO”) explains that “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.” Section 2153.02 of Manual of Patent Examining Procedure. In other words, “the exception in AIA 35 U.S.C. 102(b)(1)(B) does not necessarily remove the entire disclosure in the intervening reference from being prior art.” Id. And there is a suggestion by the USPTO that overcoming prior art via a statutory exception does not resolve issues of obviousness type double patenting.  Thus, we recommend against deliberately disclosing the invention to the public hoping to be protected under AIA § 102(b)(1)(B).


In Korea, the grace period provisions are slightly different. Under Section 30 of the Korean patents act, a disclosure of the invention within twelve months before the filing date may not become prior art that can defeat novelty or obviousness of the claimed invention, if either of two conditions is satisfied:

  1. When the disclosure was made by a person with a right to the disclosed invention, the applicant should claim a publication exception with evidence, such as the disclosed document, to the Korean Patent Office within 30 days from the filing date (see section 30(2) of Korean Patent Law); or
  2. When the disclosure was made not in accordance with the intent of the person having a right to the invention, for example disclosed by a third party, a grace period may be claimed during the response period to office actions or for three months after the receipt of the notice of allowance (see section 30(3) of Korean Patent Law).


In China, the grace period provision is considerably more limited. In China, a six-month grace period is allowed under limited circumstances (see Article 24 of the Chinese Patent Law). Specifically, within six months before the filing date, an invention for which a patent application is filed does not lose its novelty under any of the following circumstances:

  1. The invention was exhibited for the first time by the Applicant at an international exhibition sponsored or recognized by the Chinese government;
  2. The invention was made public for the first time by the Applicant at a prescribed academic or technology-related convention; and
  3. The invention was divulged by a third party without the consent of the Applicant.

The third party who divulged the invention shall have access to the invention before the filing date. On the other hand, if a person independently made the same invention and filed a patent application prior to the above-mentioned filing date, this independently-filed patent application will be considered as prior art, even it is filed within the six months before the above-mentioned filing date.


The EPO “grace period” is even more limited. While the EPO does allow inventions to be exhibited at certain recognized exhibitions (similar to points 1 and 2 in China), the Applicant must also obtain and file a supporting certificate within a set time limit to support their claim to a six-month grace period. A grace period is also available in the case of abusive disclosures occurring no more than six-months prior to the filing date (similar to point 3 in China).


For all practical purposes, the EPO and China do not have a “grace period” as this term is understood in the U.S. and Korea. It is therefore important, if global patent protection is required, to ensure that the invention is not publicly disclosed prior to filing.

Since waiting for clinical trial data is therefore not necessarily advisable, although there could be a good outcome in the United States, as in Sanofi v. Watson and Vanda v. Westward, in our next article in this mini-series, we will look at how much data is recommended for filing a pharmaceutical patent application in the U.S., Korea, EPO, and China. 

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.