The Japanese Patent Law permits exceptions to lack of novelty in special cases, for example, cases in which an invention is disclosed against the inventor’s will, an invention is disclosed due to the inventor’s conduct, etc. In order to receive the permission from the JPO, a Japanese patent application must be filed within 6 months from the date on which the invention was disclosed. In the case of a PCT application, a Japanese national phase entry must be filed within 6 months from the date on which the invention was disclosed in a foreign country.
The JPO recently agreed on the principle of extending the grace period from 6 months to 12 months, and the Japanese Patent Law will be revised in this regard probably next year.
We will keep you informed of any developments in this connection.