| Sawai Pharmaceutical Co., Ltd | |
| SB Atwork Corporation | Tokyo |
| SB C&S Corporation | Tokyo |
| SB Creative Corporation | Tokyo |
| SB Innoventure Corporation | Tokyo |
| SB Payment Service Corporation | Tokyo |
| SBC Tokyo Medical University | |
| SBI Asset Management Co., Ltd | |
| SBI Graduate School | |
| SBI Investment Co., Ltd | Tokyo |
| SBWorks Co., Ltd | |
| Scala Communications, Inc. | Tokyo |
| Scalar Corporation | Tokyo |
| School Corporation Tachibana Gakuen | |
| Science & Technology Systems Co., Ltd | Tokyo |
| Science Council of Japan | |
| Scinet Pluss, Inc. | Tokyo |
| Scohia Pharma, Inc. | |
| SCP.SOFT | Tokyo |
| Screen Holdings Co., Ltd | Kyoto |
| Scrum Software Co., Ltd | Fukuoka |
| SCSK Corporation | Tokyo |
| Scuti AI | |
| SDK | Tokyo |
| Seal Tech, Inc. | |
| SECH.ai, Inc. | |
| Secom Johshinetsu Co., Ltd | Tokyo |
| Secure Sky Technology Co., Ltd | Tokyo |
| SecureNavi Co., Ltd | Tokyo |
| SecureSoft Co., Ltd | Tokyo |
| Sees Co., Ltd | Tokyo |
| SEGA | Tokyo |
| Sega Sammy Holdings, Inc. | Tokyo |
| Seian University of Art and Design | |
| Seigakuin University | |
| Seigakuin University and Schools | Tokyo |
| Seigakuin University Graduate School | |
| Seijo Gakuen | |
| Seijoh University | |
| Seikagaku Corporation | Tokyo |
| Seikei Gakuen | |
| Seiken Co., Ltd | Tokyo |
| Seiko Epson Corporation | Nagano |
| Seiko NPC Corporation | Tokyo |
| SEIKOSHA Co., Ltd | Tokyo |
| Seikyou Internet | Tokyo |
| Seinan Gakuin University | |
| Seinan Jo Gakuin University | |
| Seirei Christopher University | |
| Seisa Dohto University | |