The duration of a lease may not exceed 50 years. Even if the contract prescribes a longer term, that term is considered to be 50 years.
賃貸借の存続期間は、五十年を超えることができない。契約でこれより長い期間を定めたときであっても、その期間は、五十年とする。
The duration of a lease may be renewed; provided, however, that the term may not exceed 50 years from the time of the renewal.
賃貸借の存続期間は、更新することができる。ただし、その期間は、更新の時から五十年を超えることができない。
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lease
賃貸借
A contract in which one party, the lessor (賃貸人), agrees to let the other use a thing and take what it yields, and the other party, the lessee (賃借人), agrees to pay rent for it and to return it when the contract ends (Civil Code, Article 601). It ends when the thing can no longer be used at all, for example because it has been destroyed (Article 616-2), and where a lease is cancelled the cancellation takes effect only from then on (Article 620). For land held in order to own a building, and for buildings, the Act on Land and Building Leases sets special rules (特別の定め) on how long a lease lasts, how it is renewed and what effect it has, among other things (Article 1).
Written by AI using Civil Code, Arts. 601, 616-2, 620 and Act on Land and Building Leases, Art. 1 as a reference.