Definition

Information that law, regulation, or government side policy requires to have safeguarding or disseminating controls, excluding information that is classified under Executive Order 13526, Classified National Security Information, December 29, 2009, or any predecessor or successor order, or the Atomic Energy Act of 1954, as amended.

Comments

A categorical designation that refers to unclassified information that does not meet the standards mentioned above but is i) pertinent to the national interests of the United States or the important interests of entities outside the federal government, and ii) under law or policy requires protection from unauthorized disclosure, special handling safeguards, or prescribed limits on exchange or dissemination. Henceforth, the designation CUI replaces Sensitive But Unclassified (SBU).

Source

NIST Glossary

NESDIS Data Management Lexicon and Related Terms 

Category

4. Data Stewardship words