Mich. Comp. Laws § 445.2502: Definitions.

Sec. 2.

As used in this act:

"Commercial e-mail" means an electronic message, file, data, or other information promoting the sale, lease, or exchange of goods, services, real property, or any other thing of value that is transmitted between 2 or more computers, computer networks, or electronic terminals or within a computer network.

"Computer network" means 2 or more computers that are, directly or indirectly, interconnected to exchange electronic messages, files, data, or other information.

"E-mail address" means a destination, commonly expressed as a string of characters, to which e-mail may be sent or delivered.

"E-mail service provider" means a person that is an intermediary in the transmission of e-mail or provides to end users of e-mail service the ability to send and receive e-mail.

"Internet domain name" means a globally unique, hierarchical reference to an internet host or service, assigned through centralized internet authorities, comprising a series of character strings separated by periods, with the right-most string specifying the top of the hierarchy.

"Person" means an individual, corporation, partnership, association, governmental entity, or any other legal entity.

"Preexisting business relationship" means a relationship existing before the receipt of an e-mail formed voluntarily by the recipient with another person by means of an inquiry, application, purchase, or use of a product or service of the person sending the e-mail.

"Unsolicited" means without the recipient's express permission. An e-mail is not unsolicited if the sender has a preexisting business or personal relationship with the recipient. An e-mail is not unsolicited if it was received as a result of the recipient opting into a system in order to receive promotional material.