Requirements for adverse possession of real property?

What the Law Says

Japanese civil law recognizes adverse possession (acquisitive prescription) as a way to acquire ownership of real property through long-term possession under specific conditions.

To acquire ownership of land through adverse possession in Japan, a person must possess the property continuously, peacefully, openly, and exclusively — and either (1) for 20 years without requiring good faith or just title, or (2) for 10 years if the possessor acted in good faith and had just title (e.g., a defective deed or mistaken belief of ownership).

Importantly, adverse possession alone does not automatically transfer legal title. The possessor must apply for registration of ownership with the Legal Affairs Bureau after the statutory period ends. Without registration, the acquisition is incomplete and unenforceable against third parties.

The Civil Code defines 'peaceful and open' possession as use that is neither by force nor in secret — meaning the possessor treats the land as their own in a manner visible to others, such as building structures, farming, or fencing.

Statutory Text

A person who has possessed another person’s immovable property peacefully and openly for twenty years acquires ownership thereof.

— Civil Code, s. 162 — Acquisitive Prescription

Statutory Text

A person who has possessed another person’s immovable property peacefully and openly for ten years, believing in good faith and without negligence that he or she has title thereto, acquires ownership thereof.

— Civil Code, s. 162 — Acquisitive Prescription

What to Do

Sources