The National Labor Relations Board made a major change in U.S. labor law when it decided that a single bargaining unit could encompass both a company's own employees and workers provided by another organization, but the impact of the ruling remains to be seen, management lawyers told Bloomberg BNA.

In Miller & Anderson, Inc., the board said it must adapt to changing patterns of industrial life. Patricia A. Smith, a partner in Ballard & Spahr's New Jersey office, told Bloomberg BNA July 15 that although she agrees the Miller & Anderson decision was part of an NLRB effort to make it easier for unions to succeed in organizing, "there is an opportunity for employers to review their employment practices" and show that a combined unit of jointly employed and solely employed workers is not appropriate.

There will likely be differences in the pay and benefits of employees who are solely employed by a "user" employer such as a manufacturer, and those provided by a staffing company or temporary agency, Smith said. Employers can certainly argue that those differences are relevant to determining whether a combined unit is appropriate, she said.