N.Y. Transportation Corporations Law § 101

§ 101. Limitation of powers. Nothing in this article shall be so\nconstrued as to permit any such corporation to engage in manufacture or\nproduction, except for its own use, of power, heat, light, supplies and\nequipment or to carry on the business of generating, selling or\ndistributing electricity for light, heat or power, nor shall the right,\noperation and use of such privileges be extended beyond the streets or\nmarginal streets bounding or occupied by the property owned or operated\nby such corporation. No railroad corporation, and no corporation or\njoint-stock association engaged in carrying on an express business,\nshall either directly or indirectly, or through the medium of a holding\ncompany or otherwise, purchase, acquire or hold, any stock, bond or\nevidence of indebtedness issued by any such corporation.\n