| Sandbox Studios | | Develops children's software and arcade titles for consoles and PCs. |
| SCS Software | | Independent developer of Rocky Mountain Trophy Hunter 3 and Shark! Hunting the Great White. |
| Semionetix | | International developer and publisher of interactive entertainment software and arcade machines. |
| Shin'en Multimedia | | Developer of such titles as the Iridion series and Maya the Bee. Game information, Game Boy Advance sound utilities, and company information. |
| Small Rockets | | Developer of downloadable PC games such as Masters of the Sky: The Red Ace, Tower of the Ancients, and Jetboat Superchamps. |
| Soft-iK | | Develops Windows CE games such as Larva Run. |
| Softgame | | Developer of PC card games such as poker and solitaire. |
| SoftSpot Software | | Developer of intellectual word games and puzzles. Titles include Letter Rack and What's Up. |
| SoftySoft | | Developer of Anarchy and Deathchase 3D. |
| Soleau Software | | Developer of family friendly non-violent strategy logic games for both Windows and Macintosh computers. |
| Sounds4games | | Sells collections of sounds to game developers. |
| spark | | Developer of Call of Duty: Finest Hour for Playstation 2, Gamecube and Xbox. |
| Sports Interactive | | Developers of sports games such as Championship Manager, CM Quiz and an EHM. |
| Strategic Studies Group | | Developers of Total War, Warlords II for the Mac, Ardennes Offence and Warlords II and III for the PC. [PC/Mac] | |
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