Updated June 17, 2026
When you wish to appeal a JPO refusal, or a dispute arises such as a third-party rights claim or infringement warning, you can contest the matter through JPO trials and court litigation.
JPO Trials & Opposition
Appeal against refusal
A trial requested to contest an examiner’s decision of refusal.
Invalidation trial
A trial seeking to invalidate a registered right (filed by an interested party).
Correction trial
A trial to correct the specification, claims, etc.
Patent opposition
Filable by anyone within 6 months of publication (no anonymous filing).
Flow of Appeals & Litigation
1
Refusal / dispute
Examination refusal, or infringement/invalidity dispute
2
JPO trialJPO Trial Board
Appeal against refusal, invalidation/correction trial, or opposition
3
Action to rescind a decisionIP High Court
Filed when dissatisfied with a JPO decision
4
Infringement suitDistrict Court (exclusive jurisdiction)
Damages/injunction for infringement
5
Final appealSupreme Court
Appeal against a high court judgment
Key Systems to Know
Evidence-collection (Sasho) system
A neutral technical expert inspects the opponent’s site to prove infringement (introduced 2020).
Damages calculation
Rules for calculating damages were enhanced (2019 amendment, considering reasonable royalties).
Rescission actions
Actions to rescind JPO decisions fall under the exclusive jurisdiction of the IP High Court.
Recent Developments (2025)
2025
AI inventorship ruling
The IP High Court held that inventors under the Patent Act are limited to natural persons (rejecting AI).
2025
Cross-border infringement
The Supreme Court recognized infringement in Japan for transmitting a program from overseas servers to users in Japan.