Spamming can take on many forms and is difficult to precisely define. Generally speaking, though, it consists of mass posting or cross-posting of unsolicited e-mail for commercial purposes. Under federal law, it’s unlawful to send junk mail by facsimile, with the possibility of civil liability of up to $500 per copy. Efforts have been made to extend this law to spam sent over the Internet, but isn’t clear if this law applies to spamming.
Some states like California have gone further. Under legislation approved in September 1998, unsolicited commercial e-mail messages must include opt-out instructions and contact information. An opt-out request must also be honored. Certain messages must also be identified in their subject lines as being advertisements. A service provider may also sue a sender of unsolicited commercial e-mail for violating the provider’s policies if the sender has actual notice of such policies and if the spam is sent out through the provider’s facilities located in California. Other states make it illegal to provide falsified routing information.