N.Y. PVH Law § 211

§ 211. Exemption from increase in local taxation. 1. A local\nlegislative body is hereby authorized, by adopting or enacting an\nordinance or local law, to exempt all or part of the real property held\nby redevelopment corporations during a maximum exemption period, which\nshall not exceed ten years, which represents an increase in any local\ntax over the maximum local tax. After the adoption or enactment of such\nan ordinance or local law, every parcel of real property held by any\nredevelopment corporation in the city shall be exempt during the maximum\nexemption period, from that portion of each and every local tax to the\nextent that such exemption has been granted by such ordinance or local\nlaw. If, during the last year of the maximum exemption period, such\nexemption is in existence on the day such local tax, or installment\nthereof, becomes a lien on such parcel of real property, such exemption\nshall extend for the full tax year for such local tax and shall not be\napportioned because of the expiration of the maximum exemption period\nduring such tax year.\n 2. For the purpose of fixing the date of commencement of the maximum\nexemption period for a group of parcels of real property in a\ndevelopment area, a city is hereby authorized, with the approval of its\nlocal legislative body, except that if there is a board of estimate in\nthe city, then with the approval of the board of estimate, to contract\nwith a redevelopment corporation to place in one or more groups the\nvarious parcels of real property therein. Such a contract may provide\nthat all of the parcels in each group may be deemed to have had a common\nstated date of acquisition by the redevelopment corporation, regardless\nof the actual date of acquisition of each parcel contained therein. Such\nagreed date of acquisition shall thereupon serve as a basis for\ncomputing the maximum exemption period for each parcel of real property\nin the group. Such agreed date of acquisition shall not be later than\nthe date of the actual acquisition of one or more parcels of real\nproperty in the group. After the making of any such contract, all of the\nparcels of real property in any such group shall be treated as a unit\nfor the purposes of the assessment and collection of each local tax, and\nthe maximum exemption period so computed shall be binding with respect\nto each local tax.\n