Michigan Compiled Laws, Chapter 339. Occupational Code § 339.6113

Sec. 1113.  (1) The department shall issue a master plumber's license to an individual who is at least 18 years old and who does all of the following:

(2) As a condition of renewal of a master plumber's license, the master plumber must demonstrate the successful completion of a course, approved by the board, concerning any update or change in the state construction code within 12 months after the update or change in that code.  This requirement applies only during or after those years that the state construction code is updated or changed.

(3) A licensed master plumber shall represent only 1 plumbing contractor at any given time.

(4) A master plumber who is also a plumbing contractor is only responsible for payment of the plumbing contractor initial or renewal license fee and is not responsible for also paying the master plumber initial or renewal license fee under section 1121(7).

(5) If a master plumber who represents a plumbing contractor ceases to represent the plumbing contractor, the master plumber shall notify the department in writing within 30 days after the date his or her representation of the contractor ceases.