Silence is Golden... Registered?
Ah, I caught up. That was fast.
A few days ago I watched a movie at an AMC theater. Before the movie started, they showed short slip telling people to be quiet while the movie is showing. The slip ended with the words "Silence is Golden®".
I was really surprised that they could register something as common as "silence is golden", especially since it's not being used outside of its usual context.
A quick google search shows this has been brought up a number of times. At least AMC has the wits not to sue anyone over it.