This following is from the Food and Drug Administration:
The U.S. Food and Drug Administration today released results from sampling of domestically manufactured dark chocolate bars and dark chocolate chips labeled as “dairy free” or with similar claims. The sampling was conducted to better understand the extent to which these products contain potentially hazardous levels of milk. The FDA is concerned about the presence of milk in dark chocolate claiming to be dairy-free because it can cause serious health consequences to consumers with milk allergy.
The FDA does not define the terms “dairy-free,”or “milk-free.” Such claims are voluntary and when used must be truthful and not misleading. Consumers with milk allergy who choose to eat dairy-free chocolate may wish to contact the manufacturers and inquire about how the product is made, including whether the product is made on equipment dedicated to making dairy-free chocolate, whether the ingredients used are free of milk, and whether the manufacturer tests its products with dairy-free claims for the presence of milk.
For more information on ingredients, go to https://www.vrg.org/ingredients/index.php