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Definition

Controlled Unclassified Information

Also known as: CUI

Controlled Unclassified Information (CUI) is unclassified information that requires safeguarding or dissemination controls under law, regulation, or government-wide policy. It is explicitly marked CUI by the originating agency and triggers NIST SP 800-171 protections — and at the contractual level, CMMC Level 2.

In more detail

CUI was created by Executive Order 13556 (2010) and implemented government-wide by 32 CFR Part 2002. The categories of information that qualify are maintained in the NARA CUI Registry — examples include export-controlled technical data, controlled technical information (CTI), naval nuclear propulsion information, personally identifiable information of contract employees.

The single clearest distinguishing feature: CUI is marked. If a document does not bear a CUI banner marking, it is not CUI in the regulatory sense — even if it is sensitive.

Primary source
NARA — CUI Registry

Related terms

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