| I-Imagine Interactive | Publisher | |
| I-Space Interactive | Developer | |
| I-cell | DeveloperPublisher | |
| I. Okuyama | Developer | |
| I.E.Game studio | Developer | |
| I.J.E. | Developer | |
| I.Magic | DeveloperPublisher | |
| I.Motion Inc. | Publisher | |
| I.O.S. Team | DeveloperPublisher | |
| I.S.C. | Developer | |
| I.S.C. Co., Ltd. | DeveloperPublisher | |
| I.T.L | Developer | |
| I.T.L Inc. | Developer | |
| I.V.O Games | DeveloperPublisher | |
| I.W.A. | Developer | |
| I3 | Developer | |
| I3uckwheat | Developer | |
| IAA | Developer | |
| IAH Games | Publisher | |
| IAmDirt | Developer | |
| IBA | Developer | |
| IBM | DeveloperPublisher | |
| IBOL | Developer | |
| IBS | DeveloperPublisher | |
| IC Contemporary | Developer | |
| IC Rainbow | Developer | |
| ICE | DeveloperPublisher | |
| ICE Software | Developer | |
| ICE Software (Alan Grier, Chris Scudds) | Developer | |
| ICE Software (Ian Morrison, Alan Laird, Alan Grier, Dave Lowe) | Developer | |
| ICE Software (Ian Morrison, Douglas Little, Alan Grier, Chris Scudds) | Developer | |
| ICE9jpn | Developer | |
| ICMationDev | Developer | |
| ICOM Simulations | DeveloperPublisher | |
| ICON Games | Publisher | |
| ICONICWARE | Developer | |
| ICS | DeveloperPublisher | |
| IChoMo | Developer | |
| ICreateMyGames | Developer | |
| ID Software | Developer | |
| IDC | DeveloperPublisher | |
| IDDK | Developer | |
| IDHAS Studios | Developer | |
| IDSA | Publisher | |
| IDSI | Developer | |
| IE Institute | DeveloperPublisher | |
| IEP_Esy | Developer | |
| IF | Developer | |
| IFCATS | Developer | |
| IGG | Publisher | |
| IGS | DeveloperPublisher | |
| IGS (JP) | Publisher | |
| IGS Games | DeveloperPublisher | |
| IGS JP | Publisher | |
| IIIIII | Developer | |
| IIopn | Developer | |
| IJK Software | DeveloperPublisher | |
| IKO Games | Developer | |
| IKStudio | Developer | |
| IKTeam | Developer | |
| IK_Knight | Developer | |
| ILCA | Developer | |
| ILIKESCIFI | Developer | |
| ILL TETEKA | Developer | |
| ILOI | Developer | |
| IMAZIC | DeveloperPublisher | |
| IMC | Publisher | |
| IMC Games Co.,Ltd. | DeveloperPublisher | |
| IMJ Entertainment | Developer | |
| IMP | Developer | |
| IMPULSE SLY | Developer | |
| IMWgms | Developer | |
| INCD021 | Developer | |
| INDIECN | Developer | |
| INDIEVIDS | Developer | |
| INF | Developer | |
| INFINITY PATHOLOGY GAMES | Developer | |
| ININ Games | Publisher | |
| INKEYE | Developer | |
| INKIVI | Developer | |
| INOS | DeveloperPublisher | |
| INTERSTELLAR INDUSTRIES | Developer | |
| INTFARM | Developer | |
| INTV | Publisher | |
| INTV Corporation | Publisher | |
| IN|Framez | DeveloperPublisher | |
| IN|Framez Technology | Developer | |
| IO | Developer | |
| IO Design Group | Developer | |
| IO Entertainment | Developer | |
| IO Interactive | DeveloperPublisher | |
| IOMO | Developer | |
| IONorth Games | Developer | |
| IOmarDev | Developer | |
| IOniverse | Developer | |
| IPalos | Developer | |
| IR Gurus | Developer | |
| IRON Games | Developer | |
| ISART DIGITAL | Developer | |
| ISCO | Developer | |