New York Consolidated Laws, General City Law - GCT § 39. Report of change in federal taxable income

If the amount of a taxpayer's federal taxable income reported on his federal income tax return for any taxable year is changed or corrected by the United States internal revenue service or other competent authority, or as the result of a renegotiation of a contract or subcontract with the United States or if a taxpayer, pursuant to subsection (d) of section six thousand two hundred thirteen of the internal revenue code,  1 executes a notice of waiver of the restrictions provided in subsection (a) of said section, the taxpayer shall report such change or correction in federal taxable income or such execution of such notice of waiver and the changes or corrections of his federal taxable income on which it is based, within ninety days after the final determination of such change, correction, or renegotiation, or such execution of such notice of waiver or as otherwise required by the administrator, and shall concede the accuracy of such determination or state wherein it is erroneous. Any taxpayer filing an amended federal income tax return shall also file within ninety days thereafter an amended return under this local law, and shall give such information as the administrator may require. The administrator may by regulation prescribe such exceptions to the requirements of this section as he deems appropriate.