Which marking indicates an individual's access requirement to classified information?

The designation that indicates an individual's access requirement to classified information is "Special access." This marking is specifically used to identify individuals who have not only been granted access to classified information but also have been given specific permissions or approvals to access certain subsets of that information based on their needs or roles.

Special access controls are crucial in the realm of national security because they help to further restrict the dissemination of sensitive information to only those who absolutely require it for their work. This requirement enhances protective measures, ensuring that classified information remains secure while allowing necessary personnel to perform their duties effectively.

In other contexts, the other markings serve different purposes: "Classified by" indicates the authority that classified the information; "Access control" refers generally to the protocols in place to manage who can access the information; and "Safeguarding requirement" outlines the specific measures necessary to protect the classified information. While relevant, these terms do not denote an individual’s requirement for access in the same focused manner that "Special access" does.