1. Companies starting with S:

      Saber Interactive
      Saffire
      Sanctuary Woods
      Sand Grain Studios
      Sandlot Games
      Santa Cruz Games
      Sarbakan
      SB Software
      SCEE
      Sci
      Secret Level
      SeekerTeam
      Sega
      Seika
      SEK
      Selectsoft
      Sensible Software
      Sentient Software
      Seppia Interactive
      Shaba Games
      Shadow Tor Studios
      Shiny
      Shockwave
      Shrapnel Games
      Sidewalk Software
      Sidhe
      Sierra
      Sigma Team
      Silicon Dreams
      Silicon Knights
      Sillysoft
      Silver Creek Entertainment
      Simon & Schuster
      SimTex
      Simulated Environment Systems
      Simulsoft
      Simutronics
      Sirius Software
      SirTech
      Ska Software
      Skunk Studios
      SkyFallen Entertainment
      Skyriver Studios
      SkyZone Entertainment
      Sleepless Software
      Slick Software
      Small Rockets
      Smayds
      SMERC Design
      Smoking Car Productions
      SNK
      Snowblind Studios
      Soft Images
      Soft Spot Micro Systems
      Softape
      Softcore Software
      Softdisk
      Softoogle
      Softsync
      Softwar III
      Software Creations
      Software Projects
      Software Toolworks
      Sold-Out Software
      SOMC
      Sony
      SourceForge
      SouthPeak Interactive
      Sozobon
      Space-Time Associates
      Sparkle Productions
      Spark
      Spectral Associates
      Spectrum Computers
      Spectrum Holobyte
      Spellbound
      Spiderweb Software
      SPIG
      Spinnaker
      SpinTop Games
      Spiral Software
      SpiteNET
      Splash Damage
      Spotlight Software
      Springboard Software
      Square Enix
      SquareSoft
      SSG
      SSI
      SSM
      Stainless Steel Studios
      Star Games
      Star Graphics
      Starbreeze Studios
      Stardock Entertainment
      Starpath Corporation
      Stars Dev Company
      StarSphere
      Steam
      Sterling Silver Software
      Sting
      Stoneware
      Storm City Entertainment
      Stormfront Studios
      Strategy First
      Strategy Lights Systems
      Subjunctive Software
      SubLOGIC
      Sucker Punch
      Sulus Games
      Sunflowers Interactive
      Sunspire Studios
      Sunstorm Interactive
      Super Fighter Team
      Supergiant Games
      Supersoft Associates
      SuperVillain Studios
      Supervillian Studios
      Suricate Software
      Surreal Software
      Sushi Quest Team
      SVG Distribution
      Sweet Tooth Games
      Sydney Development
      Symtus
      Synapse Software
      Synergistic Software
      Synware Games
      Syrox
      System 3
      Syzygy Engineering

      Note: bolded names indicate companies that released a game within the last twelve months.