ORS 73.0311: Accord and satisfaction.

The negotiation of an instrument marked “paid in full,” “payment in full,” “full payment of a claim” or words of similar meaning, or the negotiation of an instrument accompanied by a statement containing such words or words of similar meaning, does not establish an accord and satisfaction that binds the payee or prevents the collection of any remaining amount owed upon the underlying obligation unless the payee personally, or by an officer or employee with actual authority to settle claims, agrees in writing to accept the amount stated in the instrument as full payment of the obligation.