N.Y. Cooperative Corporations Law § 40

§ 40. Certificate of membership. Every corporation shall issue to each\nmember, upon full payment therefor, a certificate of membership (whether\nevidenced by stock or otherwise) which shall not be transferable\notherwise than as may be prescribed in this chapter, the certificate of\nincorporation and by-laws. The corporation may accept as full or partial\npayment a member's promissory note, but shall hold the certificate as\nsecurity for payment, without, however, affecting the member's right to\nvote unless such note is past due.\n