Many employers have employees sign confidentiality agreements aimed at prohibiting disclosure of confidential business information to third parties, and it has been widely assumed that such clauses were perfectly lawful. That assumption may no longer be accurate, however, as a recent First Circuit decision has held that confidentiality clauses in employment contracts can constitute a per se violation of employees’ protected rights under the National Labor Relations Act if the clauses can be read as prohibiting all discussions of wages, hours, and working conditions.