When licensing a patent to another party it is possible to register the license with the Japanese Patent Office. However, registering a license is not required in every case. Generally, the only licenses that need to be registered are exclusive licenses.
Exclusive licenses grant all of the powers associated with the intellectual property to a sole party to the exclusion of every other party. Therefore, without registration, other parties are not put on notice that they cannot license the intellectual property in question.
On the other hand, non-exclusive licenses do not need to be registered. Since the license is non-exclusive, other parties are also free to license the technology freely and there is no need to give them notice.
If you have any questions about registering a license with the Japanese Patent Office, please contact our office for a legal consultation.