29 C.F.R. § 452.47

Inasmuch as it is an unfair labor practice under the Labor Management Relations Act (LMRA) for any employer (including persons acting in that capacity) to dominate or interfere with the administration of any labor organization, it follows that employers, while they may be members, may not be candidates for office or serve as officers. Thus, while it is recognized that in some industries, particularly construction, members who become supervisors, or contractors traditionally keep their union membership as a form of job security or as a means of retaining union benefits, such persons may not be candidates for or hold office. 29 Whether a restriction on officeholding by members who are group leaders or others performing some supervisory duties is reasonable depends on the particular circumstances. For instance, if such persons might be considered “supervisors” 30 under the LMRA, their right to be candidates under the Act may be limited. Another factor in determining the reasonableness of a ban on such persons is the position (if any) of the NLRB on the status of the particular employees involved. If, for example, the NLRB has determined that certain group leaders are part of the bargaining unit, it might be unreasonable for the union to prohibit them from running for office. An overall consideration in determining whether a member may fairly be denied the right to be a candidate for union office as an employer or supervisor is whether there is a reasonable basis for assuming that the person involved would be subject to a conflict of interest in carrying out his representative duties for employees and rank and file union members.