Mich. Comp. Laws § 567.229: Unclaimed deposit for utility services.

Sec. 9.

A deposit, including any interest on the deposit, made by a subscriber with a utility to secure payment or any sum paid in advance for utility services to be furnished, less any lawful deductions, that remains unclaimed by the owner for more than 1 year after termination of the services for which the deposit or advance payment was made is presumed abandoned.