A state appeals court in San Francisco has upheld the state´s tough 1998 law regulating unwanted commercial e-mail popularly known as spam.

The court ruled Californians can demand that Internet spammers identify their e-mail as an advertisement and give the recipient a way to get off the company´s e-mail list.

The decision Wednesday by a three judge panel of the First District Court of Appeal reverses a lower court ruling that the law is unconstitutional.