Blank signature responsibility of IOUs: If someone else signs or seals the creditor's rights certificate or loan contract such as IOUs, receipts and IOUs, but fails to show that he is the guarantor or assumes the guarantee responsibility, or cannot be presumed to be the guarantor through other facts, he will not assume the guarantee responsibility.

legal ground

Article 20 of the Provisions of the Supreme People's Court on Several Issues Concerning the Application of Laws in the Trial of Private Lending Cases.

If another person signs or seals the creditor's rights certificate or loan contract such as IOUs, receipts, IOUs, but fails to indicate that he is the guarantor or assumes the guarantee responsibility, or cannot be presumed as the guarantor through other facts, and the lender requests him to assume the guarantee responsibility, the people's court will not support it.