Foreign Corporation
A foreign corporation with respect to a US state is a corporation formed under the laws of another country or another state. To do business in a state that is not the state in which the corporation incorporated, the business must register and pay the applicable fees and taxes in the state in which it is doing business.
For example, if a corporation is incorporated under the laws of Delaware but does business in California, it will need to qualify to do business as a “foreign corporation” in California.