The decision is about more than burger names, but when it comes to burger names, it's a big one. McDonald's on Wednesday lost a European Union trademark dispute over the Big Mac name after a top EU court sided with Irish fast-food rival Supermac's in a long-running legal battle. The EU General Court said in its judgment that the US fast-food giant failed to prove that it was genuinely using the Big Mac label over a five-year period for poultry products or restaurants. Per Reuters, that means McDonald's can't use the Big Mac label for its chicken sandwiches. What you need to know, per the AP: