For existing enterprises that have obtained tax registration certificates before the reform, if there is a change, after obtaining the 18-digit unified social credit code, the original special invoice seal will continue to be used and the original legal effect will be retained. That is, if a taxpayer obtains a "one license, one code" business license through industrial and commercial changes or certificate renewals, the special invoice seal does not need to be re-engraved, and the special invoice seal with the original 15-digit taxpayer code can continue to be used.