The document discusses the implications of a May 2013 deadline for the US to comply with a WTO ruling on country-of-origin labeling (COOL) for meat. If the US does not change its COOL rules by the deadline, Canada and Mexico may impose retaliatory trade measures. The ruling was a victory for Canada's livestock industry. US officials face challenges changing the rules to comply while Congress has been ineffective at passing legislation. The COOL rules increased costs for packers and led Canadian and Mexican producers to argue they reduced prices paid for imported animals.