According to Article 307 of the "Criminal Law Amendment (9)": In the case of arbitrarily modifying the IOU information, the so-called IOU he holds has no legal effect. The IOU was not revised because of a writing error. He fabricated the facts and will be punished.

Article 307 of "Amendment 9": Anyone who files a civil lawsuit based on fabricated facts, obstructs judicial order or seriously infringes upon the legitimate rights and interests of others shall be sentenced to fixed-term imprisonment of not more than three years, criminal detention or surveillance. A fine may be imposed concurrently or solely; if the circumstances are serious, the offender shall be sentenced to fixed-term imprisonment of not less than three years but not more than seven years and shall also be fined.

If the IOU is changed, first check whether the change involves substantive issues. If not, the change is irrelevant; if it involves substantive issues stipulated in the loan contract, then a seal should be stamped on the changed place. To prove that the changes are valid, otherwise, the changed IOU will be deemed invalid.

Extended information:

The basic elements of an IOU are as follows:

1. The borrower’s name, ID number, and address. The borrower is an individual and must sign in person. The legal validity of an IOU signed by someone else will cause disputes. For example, if Zhang San signs a loan in Li Si’s name, it will bring legal trouble to the lender.

2. The name of the lender: It is required to write the full name. It is best not to write it. Borrow code names such as Sister Zhang and Brother Li to avoid obstacles when claiming creditor's rights.

3. Write the loan amount clearly: It is best to write the currency of the amount, such as RMB, in uppercase and lowercase, to avoid disputes about unclear handwriting and unclear amount. However, Be sure to check for consistency between uppercase and lowercase letters.

4. Repayment period: There are advantages and disadvantages to the agreement on the repayment period. Write down the repayment period clearly.

5. Interest: For private loans, if there is an agreed interest rate, it will be performed in accordance with the agreement between the two parties. If there is no agreed interest rate, it will be regarded as an interest-free loan. Before the date when the creditor separately claims repayment and pays interest, the people's court generally does not support interest during this period of normal loan period.

6. Repayment method: Whether to repay the principal and interest in one lump sum or in installments, and how much should be repaid over what period, needs to be clarified.

7. Payment: Borrower’s signature, complete date (year, month, day), preferably printed by hand.

Reference materials: China National People’s Congress Network-General Principles of the People’s Republic of China and Civil Law

People’s Network-The signing dates of 6 IOUs have been changed