The originating agency assigns a declassification date, by default 10 years. After 25 years, declassification review is automatic with nine narrow exceptions that allow information to remain as classified. At 50 years, there are two exceptions, and classifications beyond 75 years require special permission.

Why do CIA documents become declassified?

The automatic declassification process increases the potential release of formerly classified national security information to the general public and researchers, enhancing their knowledge of the United States' democratic institutions and history, while at the same time ensuring that information which can still cause ...

How do I get declassified documents from the CIA?