Amazon.com Inc.'s Japan unit has been ordered to identify the writer of a book review that a court found was defamatory, a lawyer for a Tokyo-based nonprofit organization said Monday.

The Tokyo District Court ruled March 25 that the review in question was not based on fact and was damaging to the nonprofit, which the book referred to. It ordered Amazon Japan K.K. to identify the reviewer.

The ruling was finalized as the Amazon side did not appeal, lawyer Hiroaki Yamaoka said.