In Cintas Corp. v. NLRB, the Court of Appeals for the District of Columbia Circuit ruled that an employer committed an unfair labor practice under the National Labor Relations Act (NLRA) by simply publishing its policy on confidentiality, even though the rule did not expressly forbid protected discussions nor was there evidence that the rule was used to prohibit protected activity. In this case, Cintas sought to maintain confidential information through an employee handbook rule that prohibited employees from disclosing "the confidentiality of any information concerning the company, its business plan, its partners [employees]…accounting and financial matters." A separate disciplinary rule stated that an employee could be punished for violating a "confidence" or releasing confidential information without authorization.

The union filed unfair labor practice charges with the NLRB alleging that the company policy could be applied in a coercive manner interfering with the employees' right to discuss the terms and conditions of their employment with others. The company argued the language in the confidentiality policy did not explicitly prohibit employees from engaging in legally protected activity. The NLRB found in favor of the union.

On appeal, the court held that the mere maintenance of an overly broad rule chilled the exercise of Section 7 rights to engage in mutual aid and protection. Additionally, the court cited the fact that the company had made no effort in its rule to distinguish Section 7 protected behavior from violations of its company confidentiality policy, and therefore an employee could reasonably construe the policy to prohibit activity protected by the Act.

This decision is an important reminder to employers that, while protecting the confidentiality of proprietary company information is critical, policies protecting that information must be worded to avoid any ambiguity that might interfere with employees' protected rights to discuss work conditions under the NLRA.