What security feature must all prescriptions for controlled substances exhibit when photocopied?

All prescriptions for controlled substances must exhibit the word "void" when photocopied as a security feature. This is crucial to prevent any misuse or fraudulent activity associated with the prescription. By displaying "void," it ensures that if someone attempts to photocopy a prescription for a controlled substance, the copied version is rendered invalid, clearly indicating it is not an original document that can be filled at a pharmacy.

This security measure helps maintain the integrity of controlled substances prescriptions, safeguarding against potential abuse or diversion. In the context of pharmacy operations, adhering to this requirement underscores the importance of proper prescription handling and helps to maintain regulatory compliance.