Top Inventors at Sumitomo Coal Mining Co. All Time
| Rank | Name | Patents |
|---|---|---|
| 1 | Masao Tokita | 5 |
| 2 | Fumitake Nishiyama | 2 |
| 3 | Hitoshi Karasawa | 2 |
| #4 | Yoshito Miyasaka | 2 |
| #5 | Hidenobu Itoh | 1 |
| #6 | Kenji Inokuchi | 1 |
| #7 | Kunihiro Imada | 1 |
| #8 | Masataka Hiraide | 1 |
| #9 | Masatoshi Kobayashi | 1 |
| #10 | Mamoru Omori | 1 |
| #11 | Toshio Hirai | 1 |
| #12 | Yasuki Namiki | 1 |
| #13 | Akira Kidoguchi | 1 |