| OGUMA 1167286 · TMA618104 | Linking Int'l Co. Ltd. | 3 Cosmetics5 Pharmaceuticals | Registered | 2004 |
| OGIN 2147775 · TMA1187788 | an individual | 25 Clothing | Registered | 2023 |
| OCIM 2140005 · TMA1268287 | an individual | 14 Jewellery35 Advertising36 Finance+1 | Registered | 2024 |
| OCIM 2101496 · TMA1180474 | an individual | 36 Finance | Registered | 2023 |
| OGM 1951089 · TMA1144143 · design | an individual | 14 Jewellery25 Clothing | Registered | 2022 |
| OGM 1862935 · TMA1060373 | Direct Supply Inc. | 35 Advertising | Registered | 2019 |
| OGYM 1733571 · TMA943499 · design | an individual | 41 Education | Registered | 2016 |
| OXIMO 1685921 · TMA920958 | an individual | 7 Machines | Registered | 2015 |
| OGAM 1576066 · TMA870173 | Orchard Global Capital Group (S) Pte Ltd | 36 Finance | Registered | 2014 |
| OSIM 1473813 · TMA857720 · design | OSIM International Pte. Ltd. | 9 Electronics10 Medical20 Furniture+2 | Registered | 2013 |
| OSIM 1288777 · TMA689628 | OSIM International Pte. Ltd. | 10 Medical27 Carpets28 Toys | Registered | 2007 |
| OSIM 1171466 · TMA662796 | OSIM International Pte. Ltd. | 7 Machines9 Electronics10 Medical+5 | Registered | 2006 |
| OSIM 1082473 · TMA578799 · design | OSIM International Pte. Ltd. | 9 Electronics10 Medical11 Lighting+5 | Registered | 2003 |
| OKUMA 1020505 · TMA552159 · design | OKUMA FISHING TACKLE CO. LTD. | 20 Furniture28 Toys | Registered | 2001 |
| OKUMA 0474724 · TMA273684 · design | OKUMA CORPORATION | 7 Machines | Registered | 1982 |
| OGIN 2335317 | an individual | 33 Wine | Pending | 2024 |
| OSIM 2143708 | OSIM International Pte. Ltd. | 10 Medical20 Furniture | Pending | 2021 |
| OKUMA 2140356 · design | OKUMA FISHING TACKLE CO. LTD. | 28 Toys | Pending | 2021 |
| OGENA 2047772 | OGENA SOLUTIONS CANADA CORP. | 3 Cosmetics5 Pharmaceuticals7 Machines+3 | Pending | 2020 |
| OSNO 2265566 · TMA1284961 | 3097-1238 Quebec Inc. | 25 Clothing35 Advertising | Registered | 2025 |
| OSHIN 2256373 · TMA1283028 | Suzhou rizi office & stationery co.ltd | 16 Paper | Registered | 2025 |
| OZANI 2249197 · TMA1267376 | an individual | 14 Jewellery35 Advertising | Registered | 2024 |
| Oxumii 2245480 · TMA1264436 | Guangzhou Xumiao Electronic Commerce Co. Ltd. | 9 Electronics | Registered | 2024 |
| Océane 2208012 · TMA1248183 | MX PRODUCTS INC | 7 Machines11 Lighting | Registered | 2024 |
| OASMU 2206570 · TMA1241415 | SHENZHEN FENJUN INFORMATION TECHNOLOGY CO.LTD | 20 Furniture | Registered | 2024 |