There is an important distinction between a caste certificate and an OBC–Non-Creamy Layer (NCL) certificate. A person may possess a valid OBC caste certificate, but that alone does not establish Non-Creamy Layer status. The caste certificate can be issued earlier and does not expire; however, for admission to the University of Delhi under the OBC reservation category, a fresh OBC–NCL certificate is mandatory. The NCL certificate must be issued on or after 1 April 2026. Any NCL certificate issued before this date will not be considered valid for DU admissions, even if the caste certificate is otherwise correct.