The 4th Circuit has invalidated a National Labor Relations Board (NLRB) rule that had employers up in arms.

Last week, the court struck down a NLRB rule that required employers to hang posters in workplaces communicating to employees their right to unionize. The NLRB instituted the rule in 2011, to the dismay of employers, who believed the requirement violated their free speech rights.

The 4th Circuit agreed on Friday, the second court in the past two months to decide that the requirement was unlawful. The D.C. Circuit ruled similarly last month.

The ruling, some experts believe, calls into question the NLRB’s authority to create rules. A Proskauer Rose lawyer told Thomson Reuters the ruling created a “dividing line” between the NLRB’s reactive and reactive rulemaking.

“The courts are going to look very critically at rules that are proactive, whereas I think they’ll give the board more leeway with respect to rules that are reactive,” Ronald Meisburg said. Meisburg is the board’s former general counsel.

When the NLRB first announced its right-to-unionize poster requirement in 2010, it received more than 7,000 comments.

Read more about this story on Thomson Reuters.

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