A federal appeals court in Washington, D.C., today blocked the National Labor Relations Board (NLRB) from requiring American businesses to post its NLRA Employee Rights Poster by April 30, issuing a temporary injunction to stop the mandate.

The injunction follows on the heels of a federal court's decision in South Carolina this past Friday that said the board lacks the authority to mandate the poster.

The U.S. Court of Appeals for the District of Columbia now says the poster cannot be required until certain legal issues are resolved. The NLRB had no immediate public response, though the ruling has been appealed.

According to the D.C. Circuit Court of Appeals Order, briefing of the appeal is expected to be completed by June 29, 2012, and oral argument is expected to be scheduled in September 2012.

Update: Hours after the decision, NLRB Chairman Mark Gaston Pearce said of the recent rulings, “We continue to believe that requiring employers to post this notice is well within the board’s authority, and that it provides a genuine service to employees who may not otherwise know their rights under our law.” He also pledged that his agency would abide by the injunction.