| Asahi Intelligence Service Co., Ltd | Tokyo |
| Asahi KASEI AGMS Corporation | Tokyo |
| Asahi Net, Inc. | Tokyo |
| Asahi Tech Co., Ltd | Osaka |
| Asakurasoft Co., Ltd | Tokyo |
| Asama Software Corporation | Nagano |
| ASCII Corporation | Tokyo |
| ASCII.jp | Tokyo |
| Asgard Group | |
| Ash Multimedia Lab | Tokyo |
| Asia Pacific Computer Emergency Response Team | Tokyo |
| Asia Pacific Networking Group | Hiroshima |
| Asial Corporation Japan | Tokyo |
| Asiance Internet | |
| Asianux | |
| ASJ | Tokyo |
| Asp-vme | |
| Assistui | |
| ASTI Corporation | Shizuoka |
| ASTOM R&D | Saitama |
| Astrodesign, Inc. | Tokyo |
| At-Link, Inc. | Tokyo |
| Atlus Co., Ltd | Tokyo |
| Atmark Corporation | Tokyo |
| atmarkIT | Tokyo |
| Atom Co., Ltd | Tokyo |
| Atp's | Tokyo |
| Atsugi Isehara Cablenetwork, Inc. | Kanagawa |
| Atsystem | Tokyo |
| Au one net | Tokyo |
| Audio Note Co., Ltd | Tokyo |
| AUN Consulting, Inc. | Tokyo |
| Australasian Journal of Combinatorics | |
| Auto-ID Labs | Tokyo |
| AVHIFI | |
| Awing-i | |
| Azden | Tokyo |
| Azia Co., Ltd | Tokyo |
| ãŠã¦ãŒã‚‹é€šè²© | Tokyo |
| ã§ã‚“ã™ã‘ | Tokyo |
| デオデオエンジョイãƒãƒƒãƒˆ | Tokyo |
| ファーストサーãƒæ ªå¼ä¼šç¤¾ | Osaka |
| ベル ã‚½ãƒ•ãƒˆã‚¦ã‚§ã‚¢æ ªå¼ä¼šç¤¾ | Tokyo |
| ã‚¢ãƒ³ã‚«ãƒ¼ãƒ»ã‚°ãƒ«ãƒ¼ãƒ—æ ªå¼ä¼šç¤¾ | Miyagi |
| インテリジャパン | Tokyo |
| イージェーãƒãƒƒãƒˆ | Tokyo |
| ウェブæ±æµ· | Aichi |
| ã‚¨ãƒ¼ã‚¢ãƒ³ãƒ‰ã‚¨ãƒ¼æ ªå¼ä¼šç¤¾ | Osaka |
| ã‚ッズウェイ | Tokyo |
| ã‚·ãƒ•ãƒˆæ ªå¼ä¼šç¤¾ | Kanagawa |