Okay, so you're talking about this symbol? :

That's interesting, and I'll get word to Daniel. It is thought of as "original" with Daniel, but its hard to imagine that such a simple symbol is unique. Nevertheless, it may be because it has the lines of the eye extended beyond the intersecting lines for a reason.
Early forms of it was a cross between an eye and an ICHTHOUS symbol (early Christian symbol or a fish) - by removing the lines beyond the intersection on one side of the eye.
In fact - that is what Daniel was arrested for at the statue of liberty - putting those images up! He was kinda out of his head at the time...
If it's in the show, I'm sure that Groening put it in there, because he is a personal friend of Daniels as well as a supporter - and that sounds like something Matt would do. Of course he has all kinds of references to celebrities and hidden meanings throughout the whole series....