Mass. Gen. Laws ch. 255B § 18
A sales finance company may purchase a retail instalment contract from a seller on such terms and conditions and for such price as may be mutually agreed upon; and no filing of the assignment, no notice to the buyer of the assignment, and no requirement that the seller be deprived of dominion over payments upon the contract or over the vehicle if repossessed by the seller, shall be necessary to the validity of a written assignment of a retail instalment contract as against creditors, subsequent purchasers, pledgees, mortgagees or encumbrancers of the seller.
Unless the buyer has notice of actual or intended assignment of a retail instalment contract, payment thereunder made by the buyer to the last known holder of such contract shall be binding upon all subsequent holders or assignees.
Mass. Gen. Laws ch. 255B, § 18