employer (NLRA § 2(2))

The purpose of § 2(2) seems obviously to render employers responsible in labor practices for acts of any persons performed in their interests. It is an adaptation of the ancient maxim of the common law, respondeat superior, by which a principal is made liable for the tortious acts of his agent and the master for the wrongful acts of his servants. In administering this act the employer, for its purposes, should be not merely the individual or corporation which was the employing entity, but also others, whether employee or not, who are 'acting in the interest of an employer.