Japan Act on Specified Commercial Transactions (Act No. 57 of 1976) Art.59: Art. 59, 59-2 Unsolicited goods: no right to demand return (from 6 July 2021)

A seller that sends goods to a person who has not ordered them, or sends goods other than those ordered, together with an offer to sell them, cannot demand their return (the recipient may dispose of them at once), except where the recipient would conclude the contract for business; a seller that sends goods falsely claiming a contract was concluded likewise cannot demand their return.