The National Labor Relations Board says that it plans to file a civil complaint against Thomson Reuters, saying that illegally reprimanded an employee after she sent a tweet criticizing the company's management. The NLRB says that the company violated the reporter's rights by reprimanding her for discussing working conditions with a supervisor. The company says that they do not believe that the employee was disciplined, and that Reuters has straightforward social media guidelines. The case would be the first federal labor case to involve Twitter. In November, the NLRB ruled that posting on Facebook was protected as concerted activity.
See "Labor Panel to Press Reuters Over Reaction to Twitter Post", Steven Greenhouse, The New York Times, April 6, 2011