Why is Walt Disney’s signature on Star Wars?

Look, kids! Vague, controllable versions of things you love! Signed by a corpse who had no part in any of it! BUY BUY BUY!!!
Not just his name; his signature. As though he was the architect of its design. Walt Disney created Mickey Mouse and Donald Duck, right? Tinkerbell, sparkly glitter, and magic castles. Horrible TV-movies every Sunday. That’s Walt Disney. Around 1980, I was into Star Wars to get away from all that corny shit.
Now you’re telling me it’s Walt Disney’s property?