A membership purchase agreement is the type of agreement entered into when an ownership interest in an LLC is being bought and sold. It is critical to enter into a written contract to protect the buyer from any current or past liabilities or liens as well as protect the seller from any future encumbrances. Some of the key provisions of a membership purchase agreement dictate the purchase price, payment schedule, interest rates, and the ramifications for any violations of the agreement. It is important for any membership purchase agreement to be executed with a promissory note, if the sale is not a cash sale, meeting minutes showing the sale, and an amendment to the operating agreement showing new ownership and management roles.