California's anti-spam law requires unsolicited messages to be labeled as advertisements and to include an address or toll-free phone number recipients can use to tell the sender to stop sending documents. In June 2000, a San Francisco Superior Court judge ruled that the law violated the dormant Commerce Clause of the U.S. Constitution by placing inconsistent restrictions on interstate use of the Internet. In January, a California appeals court upheld the state law, reversing the earlier decision. --Stefanie Olsen
