29 U.S.C. § 522

(a) It shall be unlawful to carry on picketing on or about the premises of any employer for the purpose of, or as part of any conspiracy or in furtherance of any plan or purpose for, the personal profit or enrichment of any individual (except a bona fide increase in wages or other employee benefits) by taking or obtaining any money or other thing of value from such employer against his will or with his consent.

(b) Any person who willfully violates this section shall be fined not more than $10,000 or imprisoned not more than twenty years, or both.