An agency official with statutory or operational authority for specified information and responsibility for establishing the controls for its generation, collection, processing, dissemination, and disposal.
Sources:
NIST SP 800-30 Rev. 1
under Information Steward
from
CNSSI 4009
NIST SP 800-37 Rev. 2
NIST SP 800-39
under Information Steward
from
CNSSI 4009
NIST SP 800-53 Rev. 5
from
NIST SP 800-37 Rev. 2