29 U.S.C. § 104: Enumeration of specific acts not subject to restraining orders or injunctions

Ceasing or refusing to perform any work or to remain in any relation of employment; Becoming or remaining a member of any labor organization or of any employer organization, regardless of any such undertaking or promise as is described in section 103 of this title ; Paying or giving to, or withholding from, any person participating or interested in such labor dispute, any strike or unemployment benefits or insurance, or other moneys or things of value; By all lawful means aiding any person participating or interested in any labor dispute who is being proceeded against in, or is prosecuting, any action or suit in any court of the United States or of any State; Giving publicity to the existence of, or the facts involved in, any labor dispute, whether by advertising, speaking, patrolling, or by any other method not involving fraud or violence; Assembling peaceably to act or to organize to act in promotion of their interests in a labor dispute; Advising or notifying any person of an intention to do any of the acts heretofore specified; Agreeing with other persons to do or not to do any of the acts heretofore specified; and Advising, urging, or otherwise causing or inducing without fraud or violence the acts heretofore specified, regardless of any such undertaking or promise as is described in section 103 of this title .