Fast-food workers in the Charleston area held a rally Thursday following the National Labor Relations Board saying this week that McDonald's, the world's biggest hamburger chain, could be named as a joint employer in several complaints by worker groups at restaurants owned by franchisees.

The NLRB decision is seen as pivotal because it could expose McDonald's Corp. to liability for a wide range of working conditions in those locations. It also comes amid protests for higher pay that have gone national, with labor groups calling for pay of $15 an hour and the right to unionize.