Our December 2010 Employment Law Note discussed several charges that had been brought by the National Labor Relations Board (“NLRB”) against employers for maintaining social media policies the NLRB believed infringed on protected rights. Specifically, under the National Labor Relations Act (“NLRA”), which applies to union and non-union employers alike, employers are prohibited from taking adverse action against employees for engaging in “protected concerted activity,” including activities for the “mutual aid or protection” of fellow employees.