Derivation (or acquisition) of U.S. citizenship occurs when a person born outside the United States to a U.S. citizen parent or parents can establish a claim of U.S. citizenship depending on the year they were born, their legal status at the time the claim is made, their parents’ previous residency in the United States, and other requirements.

Sometimes a person will be a U.S. citizen and not even know it. Being able to derive citizenship depends on a number of factors, such as which parent was a U.S. citizen, where the parent lived, and whether or not the child was born in or out of wedlock.