Yeah, the rights to Scooby Doo are really complicated for some reason. It used to be Scooby (and all the Hannah Barbera characters) were in the chain of "Top Value Parks" (Kings Island, Kings Dominion, etc...) until Paramount bought them and they populated those parks with Nickelodeon characters. At the same time SOME of the Six Flags parks got Scooby Doo because the Hannah Barbera studio was purchased by Ted Turner just before he merged all his assets with Warner Brothers. Even then, only some of the Six Flags parks got rights to use Scooby depending on where they were located in relation to other entities that had rights to use them. I assume that Universal got some rights for a certain geographic area to use Scooby and the related trademarks (they have a Mystery Machine that had to have been licensed as well), and I'm sure if they wanted to they could expand that license. The fact that they have been working so closely with Warner Brothers on HP may have led to discussions of other licenses (like the other HB characters, more Scooby, etc.).