A federal appeals court has ruled that the National Labor Relations Board (NLRB) can't force businesses to display posters informing their employees of their right to form a union.

The court said the NLRB mandate violated free speech rights because the government "selected the message and ordered its citizens to convey that message."

Under the NLRB poster rule, most private employers would have had to display 11" x 17" posters advertising employees' union-organizing rights. If at least 20% of a firm's workforce did not speak English, the business would have had to post the notice in multiple languages.

An employer's failure to display the poster would have been considered an unfair labor practice.

The rule was supposed to have taken effect on April 30, 2012, but was challenged in court by the National Association of Manufacturers (NAM) and other business organizations. According to Jay Timmons, NAM's president and CEO, "The ultimate result of the [rule] would be to create hostile work environments where none exist."

The NLRB's last recourse to save the poster rule is now an appeal to the U.S. Supreme Court.