The United States Court of Appeals for the D.C. Circuit has held that confidentiality provisions in an employee handbook violated the National Labor Relations Act (NLRA) because employees could "reasonably construe" the provisions to prohibit them from discussing the terms and conditions of their employment with other employees, even though the provision did not expressly prohibit such discussions. N.L.R.B. v. Cintas Corp., 2007 U.S. App. LEXIS 6075 (D.C. Cir. 2007). Significantly, this decision applies to non-unionized employers as well as unionized employers.

Please see this Mintz Levin Advisory for the NLRB ruling and the D.C. Circuit Decision.