The Korean Patent Grace Period: Requirements for Foreign Applicants

Article 30 of the Korean Patent Act provides a 12-month exception for specified disclosures by the person entitled to obtain the patent and for disclosures made against that person's intention. The exception prevents the qualifying disclosure from being used under the novelty and inventive-step provisions; it does not move the filing date.

A foreign priority application does not by itself extend the Article 30 period. The Korean application, or a PCT application that will enter Korea, should be filed within 12 months after the disclosure.

Qualifying disclosures

Disclosures that may qualify include an inventor's paper or conference presentation, a company website or press release, a trade-show demonstration, a sale or offer, a thesis, and a disclosure by a person who obtained the invention from the right holder. A leak or other disclosure made against the right holder's intention may also qualify.

Article 30 excludes disclosures made through publication of a patent application or registration under a treaty or statute. It also does not remove unrelated prior art or an independent third party's earlier filing.

Calculation of the 12-month period

The period runs from the qualifying disclosure. The date should be calculated from the earliest time the technical content became publicly available.

For an online disclosure, the evidence should preserve the URL, timestamp, archived content, access settings, and first-public-access date. For a presentation, trade show, sale, or offer, the record should include the material disclosed, date, audience, access conditions, invoices, and any confidentiality terms.

Foreign priority and Korean filing dates

If an invention is disclosed publicly on March 1 and a US provisional application is filed on April 1, a Korean or PCT filing made after the following March 1 falls outside the 12-month Article 30 period even if it is still within the Paris priority year measured from the US filing.

The priority period and the Korean grace period are separate. The priority claim does not replace the Korea-relevant filing required by Article 30.

Statement and supporting documents

For a voluntary disclosure under Article 30(1)(1), the applicant should state the claim to the exception in the application and submit supporting documents within 30 days after filing. The documents should identify the discloser, the relationship to the applicant, the date and manner of public availability, the technical content disclosed, and the basis for the exception.

The Act permits specified later correction periods upon payment of a surcharge, but these periods should not be used as the filing plan. For a PCT national-phase application, the statement and proof are submitted under the special timing rule tied to the Korean national-phase reference date.

For a disclosure made against the right holder's intention, the applicant must prove the unauthorized disclosure and the relevant relationship and circumstances.

Limits of the exception

• It does not restore rights in another country.
• It does not defeat an independent third party's earlier patent filing or publication.
• It does not extend the 12-month period.
• It does not correct an invalid priority claim.
• It does not add subject matter omitted from the patent application.
• It does not determine whether a disclosure was enabling or subject to confidentiality.

A disclosure made under an effective confidentiality obligation may not be public prior art, but the agreement, access restrictions, and conduct must support that conclusion.

Response to an accidental disclosure

1. Preserve the disclosed content, date, audience, URL, and access conditions.
2. Identify all related disclosures and the earliest public date.
3. Compare the disclosed technical content with the proposed claims.
4. Stop further disclosure where possible without altering evidence.
5. File a Korea-relevant application promptly.
6. Prepare the Article 30 statement and proof with the filing.
7. Review the effect of the disclosure in each intended filing country.

Official reference

• MOIP guidance on the Patent Act Article 30 disclosure exception
• Korean Patent Act

Related guidance

• The Complete Guide to Filing a Patent in South Korea for Foreign Applicants
• PCT National Phase Entry in Korea: The 31-Month Deadline, Documents and Translation
• Direct Filing vs. PCT National Phase Entry in Korea

This article provides general information and does not constitute legal advice. The disclosure date, filing route, and Article 30 procedure should be reviewed for each application.