1. (a) For purposes of article 9-A, a corporation will be treated as a DISC if it meets the requirements of subsection (a) of section 992 of the Internal Revenue Code. At the time it files an election to be treated as a DISC pursuant to paragraph (1) of subsection (b) of section 992 of the Internal Revenue Code, the corporation must also file a copy of such election with the New York State Department of Taxation and Finance, Processing Division, Corporation Tax Registration Processing Unit, Building 8, State Campus, Albany, N.Y. 12227.
2. (b) For purposes of article 9-A, a DISC is either a “tax exempt DISC” or a “taxable DISC.” For any taxable year during which a corporation does not meet the requirements for treatment as a DISC, it will be treated in the same manner as any other taxpayer subject to tax under article 9-A.
3. (c) The term former DISC refers, with respect to any taxable year, to a corporation which is not a DISC during such year but was (or was treated as) a DISC for a prior taxable year. However, a corporation will not be considered a former DISC for a taxable year unless such corporation has, at the beginning of such taxable year, undistributed previously taxed income or accumulated DISC income.

Tax Law, §§ 208(1) and (9)(i), 209(6)