Alright a little background.
Dreamworks Pictures and Dreamworks Animation were originally under one company Dreamworks SKG. Dreamworks SKG decided to spin off and make Dreamworks Animation independent. This is when they started doing the deal with Paramount for distribution followed by 20th Century Fox. Dreamworks Animation was about to go under so Jeffrey Katzenberg put up feelers and Comcast bought it. As for Dreamworks Pictures, Disney was distributing their films and the deal wasn't making Disney as much money as they would like and Disney already had a crowded film schedule...Spielberg decided to get multiple investors (Himself, Ali Baba [Chinese], Universal [United States], Reliance [India], and eOne [UK]) to create Amblin Partners which is three studios, Dreamworks Pictures for mainstream popular release films, Participant for social reform films, and Amblin Entertainment for everything else with Universal being the main distributor.
So with this, Universal being a partial owner of Amblin, you would think they would own the rights. Nope. For example, Gremlins. Gremlins is an Amblin property, however, Warner holds the Trademark.
The easiest Dreamworks Classic example is She-Ra. While Universal has rights to She-Ra, Mattel is the ultimate property holder and decision maker in regards to that IP.