Legal analysis: If the parties conclude a contract in written form, the contract shall be established when both parties sign or seal it. Therefore, the loan contract is established when both parties sign or seal it. When the borrower/debtor writes down the IOU and signs his own name, the IOU has been established and has legal effect, and does not need the signature of a third party.

Legal basis: Article 97 of the Civil Procedure Law of People's Republic of China (PRC). If an agreement is reached through mediation, the people's court shall make a conciliation statement. The conciliation statement shall specify the claim, the facts of the case and the result of conciliation. The conciliation statement shall be signed by the judge and the clerk, stamped with the seal of the people's court and served on both parties. The conciliation statement has legal effect after being signed by both parties.