N.Y. Est. Powers & Trusts Law § 13-4.7

§ 13-4.7 Ownership on death of owner\n On death of a sole owner or the last to die of all multiple owners,\nownership of securities registered in beneficiary form passes to the\nbeneficiary or beneficiaries who survive all owners. On proof of death\nof all owners and compliance with any applicable requirements of the\nregistering entity, a security registered in beneficiary form may be\nreregistered in the name of the beneficiary or beneficiaries who\nsurvived the death of all owners. Until division of the security after\nthe death of all owners, multiple beneficiaries surviving the death of\nall owners hold their interests as tenants in common. If no beneficiary\nsurvives the death of all owners, the security belongs to the estate of\nthe deceased sole owner or the estate of the last to die of all multiple\nowners.\n