Legal basis: Article 30 of the Measures for the Administration of Invoices in People's Republic of China (PRC), the units and individuals that issue invoices shall keep the invoices in accordance with the provisions of the tax authorities and shall not damage them without authorization. Invoice stubs and invoice registers that have been issued shall be kept for five years. After the expiration of the preservation period, it shall be destroyed after inspection by the tax authorities. The tax authorities may impose a fine of less than 1 10,000 yuan if the lost stub fails to save the invoice as required.