Kantor on 17 October 2009
capcom : Street Fighter series, I guess.
ubisoft : Splinter Cell series
square-enix : n/a
namcobandai : Tekken series
mistwalker : n/a
rare : Goldeneye 007
nintendo : Zelda series
ea : Burnout series (before Paradise)
activision : Call of Duty series
id software : Doom
from software : Looks like it would be Demon's Souls, but I haven't played it.
sega : Sonic the Hedgehog series (back when it was good)
konami : Metal Gear Solid 4
EDIT:
Blizzard: Warcraft III
Sony: God of War series AND Shadow of the Colossus (tie)
2K: BioShock
EDIT 2, to make Ronster happy (kind of):
Valve: Left 4 Dead.
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