Well let me clear something up. 20th Century Fox is owned by 21st Century Fox which was acquired by Disney recently. But while 20th Century Fox is owned by 21st, 20th owns the Alien rights, as well as the rights to the first six Star Wars films. However, while 20th Century Fox will never lose the rights to the original 1977 Star Wars film, the fate of the rest of the franchise remains to be seen. That is why, on TV broadcasts of the first six films, we only hear the 20th Century Fox fanfare at the beginning of A New Hope.