Classified National Security Information Protection Act Article 31

After information is declassified, the original declassification authority shall publish the reason for declassification and notify the relevant agencies.All original and reproduced classified information shall be marked conspicuously to put users on notice of its current declassification status and necessary declassifying measures.
中文原文 國家機密保護法第31條
國家機密解除後,原核定機關應將解除之意旨公告,並應通知有關機關。
前項情形,原核定機關及有關機關應在國家機密之原件或複製物上為解除機密之標示或為必要之解密措施。

English translation for reference only; the Chinese text prevails. Not legal advice.