Issued Patents All Time
Showing 1–6 of 6 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4630969 | Artificial island | Masanao Oshima | 1986-12-23 |
| 4571125 | Floating offshore structure | Masanao Oshima, Hitoshi Narita, Hiroshi Tabuchi | 1986-02-18 |
| 4519728 | Floating offshore structure | Masanao Oshima, Hitoshi Narita, Hiroshi Tabuchi | 1985-05-28 |
| 4505618 | Marine riser protector for use on offshore oil drilling rigs in icy waters | — | 1985-03-19 |
| 4326822 | Artificial island for installing oil drilling equipment in ice covered sea areas | Masanao Oshima | 1982-04-27 |
| 4295758 | Working platform for oil drilling operations in ice covered sea areas | — | 1981-10-20 |