1st Party: - Nintendo, then Sony
3rd Party - Capcom, then Square

First party: Nintendo, 90% of all games I have ever bought is published by Nintendo, so with a quick assumption I came to that conclusion.

Third party: EA

Runner up: Sony

First Party-Nintendo
Third Party-SQEX

If it's all time, then it's Nintendo, then Sony then Microsoft for me. (Regarding First party).

I have no clue regarding third party. Perhaps Konami? I don't know. I've also had Sega in mind.

As a child mostly EA I think with Need For speed underground, The Godfather, Medal of Honor, Command and Conquer, Star Wars games (PSP and PS2) but since PS3 it became mostly Sony games. First I had Ratchet & Clank, then my two big games I bought Simultaneously were Motorstorm Pacific Rift and Resistance 2, since then I bought most of the Sony exclusives.

First party would be far and away Nintendo. For third party it would be tough. Konami, Capcom, EA, Activision... it's hard to say. I've played a lot of Square, but mostly just FF. I played more different titles when I was younger, so Konami and Capcom were kings in the NES days. Now I play mostly just a few titles that I really like.

Sony

SquareSoft/Enix by miles...

First party is Sony for sure, so I voted them. I buy almost every first party game from Sony and I enjoy the great majority. I'll only list some of them that consumed a lot of my time. I'm not going to list all the games, but titles such as the following took up a lot of my time. Note that some are not exactly owned by the holders (lke Crash), but since they were published by them at the time I'll list them still.

Gran Turismo
God of War
Spyro
Crash
Bloody Roar (1 and 2 before Sony dropped publishing).
Uncharted (especially 2 online)
Soul Sacrifice on Vita (about 150 hours so far)
PSASBR (before the online went bad)
etc etc etc

Nintendo would be a close second, mainly because of 2 games in one franchise (Smash), but I played the following a LOT

Smash Bros 64
Smash Bros Melee
Pokemon

Third Party would be Capcom. I may not dig them much now, but I played a LOT of their games over the years

Devil May Cry (I beat this game over 100 times no joke)
DMC2 (beat this one over 50)
DMC3 (over 100)
Street Fighter 2
Street Fighter EX Plus Alpha
Street Fighter EX 2
Street Fighter EX 3
Street Fighter Alpha 1, 2 and 3
Super Street Fighter 4
Marvel Vs Capcom 1,2 and 3
CAPCOM vs SNK 2
Viewtiful Joe
Resident Evil 4
Xmen: Children of the Atom
Xmen vs Street Fighter
Tech Romancer
Power Stone 1 and 2



Runner up would be Konami

Every Metal Gear Solid Game. Nothing else from them really. I play Castlevania now and again.

1st Party: Nintendo followed by Sega
3rd Party: Not a clue...maybe Konami or Capcom

Hard question.

1st party:

Nintendo_ Mario platformer (both 2D and 3D), Mario Kart, Zelda, Metroid, Donkey Kong, Kirby, F-Zero, Advance Wars (Battallion Wars inlcuded), Smash Bros, Endless Ocean, Xenoblade Chronicles and Disaster: Day of Crisis. And some others that I may be forgetting.

Sony (list from wikipedia)_ Gran Turismo, God of War, Crash Bandicoot, Jak and Daxter, Wipeot, Dark Cloud ... and I think that's it. I've also played Lemmings, but I don't know if I should include it or not.

MSoft_ Age of Empires, Halo, Forza, Gears of War. Probably more, but I don't remember.

3rd party:

I'm not sure. Maybe Capcom (list from wiki)_ 1941, Ghouls 'n' Ghosts, Street Fighter, Final Fight, Mega Man, Onimusha, Devil May Cry, Lost Planet, Zack&Wiki, Monster Hunter.