N.Y. EPT Law § 11-A-4.3

§ 11-A-4.3 Business and other activities conducted by trustee\n (a) If a trustee who conducts a business or other activity determines\nthat it is in the best interest of all the beneficiaries to account\nseparately for the business or activity instead of accounting for it as\npart of the trust's general accounting records, the trustee may maintain\nseparate accounting records for its transactions, whether or not its\nassets are segregated from other trust assets.\n (b) A trustee who accounts separately for a business or other activity\nmay determine the extent to which its net cash receipts must be retained\nfor working capital, the acquisition or replacement of fixed assets, and\nother reasonably foreseeable needs of the business or activity, and the\nextent to which the remaining net cash receipts are accounted for as\nprincipal or income in the trust's general accounting records. If a\ntrustee sells assets of the business or other activity, other than in\nthe ordinary course of the business or activity, the trustee shall\naccount for the net amount received as principal in the trust's general\naccounting records to the extent the trustee determines that the amount\nreceived is no longer required in the conduct of the business.\n (c) Activities for which a trustee may maintain separate accounting\nrecords include:\n (1) retail, manufacturing, service, and other traditional business\nactivities;\n (2) farming;\n (3) raising and selling livestock and other animals;\n (4) management of rental properties;\n (5) extraction of minerals and other natural resources;\n (6) timber operations; and\n (7) activities to which 11-A-4.14 applies.\n