SDCL § 43-42-5: Debtor unaware of assignment--Acquittance by good faith payment to assignor, creditor, subsequent purchaser, or other assignee or transferee.

In any case where, acting without knowledge of an assignment described by § 43-42-4, the debtor in good faith pays all or part of such account to the assignor, or to such creditor, subsequent purchaser, or other assignee or transferee, such payment shall be acquittance to the debtor to the extent thereof, and such assignor, creditor, subsequent purchaser, or other assignee or transferee shall be a trustee of any sums so paid and shall be accountable and liable to the prior assignee therefor.