In the United States, the first to use a mark establishes a prior right in the mark, and can exclude all subsequent users of confusingly similar marks. This is in contrast to most other countries, which grant priority based on the first to register a mark. The different systems present complications for those starting their businesses in the U.S. and expanding later into other countries. Sometimes the first to use in the U.S. is thwarted by another company in a different country who had the foresight to register the mark in the foreign country first. When this happens, the U.S. trademark owner may have to pay a licensing fee just to use its U.S. mark in another country. Worse yet, the U.S. trademark owner may be entirely prevented from using the mark in that country.