Which Spanish football club has a policy that only people native to the Basque region can play for them?

Athletic Club (Basque: Athletic Kluba), also commonly known as Athletic Bilbao (Basque: Bilboko Athletic Kluba), is a professional football club, based in Bilbao, Basque Country, Spain.

The club is known for its cantera policy of bringing young Basque players through the ranks, as well as recruiting top Basque players from other clubs (like Joseba Etxeberria and Javi Martínez). Athletic's official policy is signing professional players native to or trained in football in the greater Basque Country, including Biscay, Gipuzkoa, Álava and Navarre (in Spain); and Labourd, Soule and Lower Navarre (in France). Since its foundation, Athletic has played exclusively with players meeting the criteria to be deemed as Basque players, and has been one of the most successful teams of La Liga. This can be seen as a unique case in European football; it has gained Athletic both admirers and critics. The club has been praised for promoting home grown players and club loyalty. Athletic is one of only three professional clubs in Spain in La Liga (the others being Real Madrid, and Barcelona) that is not a sports corporation; it is owned and operated by its club members.