The long, litigious and tangled history of the Deferred Action for Childhood Arrivals program took another turn Wednesday when a federal appeals court ruled the program is illegal.

However, the 5th U.S. Circuit Court of Appeals also allowed the nearly 600,000 people in the program to avoid deportation, according to The New York Times.

DACA was created by the stroke of a pen in 2012 by then-President Barack Obama. Its purpose was to allow illegal immigrants who entered the country as children along with their parents to avoid deportation.