Last Friday, the NLRB reversed a 2011 decision in Specialty Healthcare and Rehabilitation Center of Mobil that held an employer must demonstrate that the employees it seeks to include in a given bargaining unit share “an overwhelming community of interest” with the employees already in the unit suggested by the union. The decision made it easier for unions to organize employees by allowing them to focus on smaller groups of employees that share a specific occupation, rather than having to organize several different types of workers at a given facility. On Friday, in a 3-2 ruling in PCC Structurals, INC, the NLRB reverted to the original “community of interest” test, which determines the size and extent of a bargaining unit based on a broader set of factors. The reversal will make it substantially more difficult for unions to organize employees.
See "National Labor Relations Board Overrules Controversial Decision Facilitating Union Organizing of Micro-Units", Daniel B. Paternak, The National Law Review, December 18, 2017