N.Y. Comp. Codes R. & Regs. tit. 20, § 529.4
(2) Cross-reference:
(iii) Upon approval of the application, the Taxpayer Assistance Bureau will issue to each qualifying international organization a numbered exempt organization certificate.
Cross-reference:
For applicable general regulations, including denials and revocations, see subdivision (j) of section 529.1 of this Part.
(4) An exempt organization certification is properly completed when it contains the:
(v) date the certification was issued.
(b) As vendor.
Tax Law, § 1116(a)(3)
(a) As purchaser.