Identifying material

Definition
Identifying material (ID material) is

"a]n alternative deposit copy permitted or required under U.S. Copyright Office regulations for registration, such as photographs submitted in lieu of three-dimensional works of visual arts; redacted versions of secure tests; portions of computer source code, etc. Identifying material is material that adequately represents the authorship claimed in an unpublished or published work, whether the regulations permit a substitute or whether it is a required substitute for the actual work, as in the case of most three-dimensional visual arts works."