29 C.F.R. § 452.44 Dual unionism.
Title 29 - Labor
While the Act does not prohibit a person from maintaining membership or holding office in more than one labor organization, it would be considered reasonable for a union to bar from candidacy for office persons who hold membership in a rival labor organization.
Title 29: Labor
PART 452—GENERAL STATEMENT CONCERNING THE ELECTION PROVISIONS OF THE LABOR-MANAGEMENT REPORTING AND DISCLOSURE ACT OF 1959
Subpart E—Candidacy for Office; Reasonable Qualifications
§ 452.44 Dual unionism.