Michigan Compiled Laws, Chapter 554. Real and Personal Property § 554.213

Sec. 3.  The term “trust mortgage” as used in this act, means and includes, among other forms of trust mortgages, any mortgage given to any person or corporation engaged in the business of financing or refinancing buildings or building enterprises, securing a note, notes, bonds or obligations, and which by its terms contemplates a sale thereof in part or parts and which is actually sold in part or parts in form of certificates of participation or by assignments of undivided interests therein.