DreamWorks Animation SKG is an American animation studio, producing primarily feature animated films. DreamWorks Animation was formed by the merger of the feature animation division of DreamWorks SKG and Pacific Data Images (also known as PDI). Originally formed under the banner of DreamWorks SKG, it was spun-off into a separate public company in 2004.


Its films are currently distributed by Paramount Pictures (in turn owned by Viacom) who acquired the rest of DreamWorks SKG in February of 2006. DreamWorks Animation maintains two studios: the original DreamWorks feature animation studio in Glendale, California and the PDI studio in Redwood City, California in the Silicon Valley region.

In 1997, DreamWorks SKG signed a co-production deal with PDI to form PDI's subsidiary PDI, LLC (PDI owned 60% of PDI, LLC while DreamWorks SKG owned 40%). PDI, LLC would produce computer-generated feature films beginning with Antz (1998). In the same year DreamWorks SKG produced The Prince of Egypt using traditional animation techniques.


In 2000, DreamWorks SKG created a new business division, DreamWorks Animation, that would regularly produce both types of animated feature films.
The traditionally animated feature films were produced by the division's Southern California branch. DreamWorks SKG acquired majority interest (90%) in PDI, reforming it into PDI/DreamWorks, the Northern California branch of its new business division.
The business division separated from its parent in 2004, forming DreamWorks Animation SKG, Inc. and purchasing the remaining interest in PDI as well as its subsidiary PDI, LLC.
Since 2004, DreamWorks Animation is dedicated solely to producing CG animated films in-house. No more traditional 2D animation is expected.


DreamWorks Animation also has a partnership with Aardman Animations, a stop-motion animation company in Bristol, England. This partnership has DreamWorks participating in the produciton of stop-motion films in Bristol, and also has Aardman participating in some of the CG films made in the US.

http://en.wikipedia.org/wiki/DreamWorks_Animation_SKG

The only major studios DreamWorks have not co-released movies with are :

Metro-Goldwyn-Mayer

and

Walt Disney Pictures.

this is not surprising, given Disney's hostile relations with DreamWorks co-founder Katzenberg: when Disney’s then-second in command, Frank Wells, died in a helicopter crash, CEO Michael Eisner refused to promote Katzenberg, firing him after he pushed the issue. Katzenberg then filed a lawsuit against Disney to recover money he felt he was owed and settled out of court for an estimated $100 - $250 million (the actual amount remains secret).