1. EA Canada
2. Nintendo
3. Konami Corporation
4. Maxis
5. Traveller's Tales
6. Rockstar Leeds
7. Ubisoft France
8. Yuke's
9. EA Redwood Shores
10. Ubisoft Montreal
11. Amaze Entertainment
12. Treyarch
13. EA UK-Criterion
14. London Studios
15. Crystal Dynamics
16. Epic Games
17. Capcom
18. Sports Interactive
19. Radical Entertainment
20. Relentless Studios

Source