Osaka District Court, Reiwa 4 (Wa) 11405 [Heterocyclic derivatives] <Presiding Judge Takemiya>
更新日：10月3日
Article information
Article type: Case note
Classification: Patents
Issues: Employee inventions; reasonable remuneration
First published on this site: 2026-10-03
Court: Osaka District Court
Case number: Reiwa 4 (Wa) 11405
Display/classification checked: 2026-10-03
Osaka District Court, Reiwa 4 (Wa) 11405 [Heterocyclic derivatives] <Presiding Judge Takemiya>
[Employee-invention remuneration] Approximately JPY 94 million awarded.
* The employee-invention rules were redacted and their details are unclear, but they did not apply to this invention.
⇒ Patent Act before the 2004 amendment.
Reason: Although the defendant had employee-invention rules, no agreement to apply them to a case such as this invention was established. Statutory “reasonable remuneration” therefore had to be calculated.
Own exploitation (domestic sales):
Excess sales × hypothetical royalty rate (5.9%) × (1 − employer's contribution of 99%) × co-inventor's share (1/3).
Third-party exploitation (license income):
License income × (1 − employer's contribution of 99%) × patent contribution (25%*) × co-inventor's share (1/3).
* The license agreement also covered know-how and data provision, so the patent itself was assigned a 25% contribution.
(Excerpts from the judgment, translated)
The employee-invention rules: [redacted].
However, those rules did not provide that they applied to inventions outside the categories specified in them, such as the invention at issue. Nor was there sufficient evidence in the record to establish an agreement between the plaintiff and defendant to apply the rules to such inventions.
Revision history
Revision history is maintained by appending entries.
2026-10-03: First published on this site; classification, article information, and consultation link added.
