An independent union is a trade union that represents workers in one plant or company and is free of employer control. (This includes a union representing workers in more than one plant located in two or more states but employed by the same employer.) A national independent union is a union of a national character not affiliated with the AFL or CIO; a local independent union is one of a local character not affiliated with the international union having jurisdiction over that branch of industry.
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Independent union Wikipedia(Text) CC BY-SA