| ODDIO 1386506 · TMA774446 | an individual | 33 Wine | Registered | 2010 |
| ODOO 1687627 · TMA978185 | an individual | 9 Electronics35 Advertising41 Education+1 | Registered | 2017 |
| ODD 1594928 · TMA915041 · design | MGMA Ventures Ltd. | 33 Wine | Registered | 2015 |
| ODO 0724217 · TMA447575 | CBS Studios Inc. | 3 Cosmetics9 Electronics14 Jewellery+6 | Registered | 1995 |
| ODO 2156068 | Sixteen South Studios Limited | 9 Electronics16 Paper25 Clothing+2 | Pending | 2021 |
| Oduio 2187071 · TMA1223206 | Shenzhen Xingaichen Trading CO. LTD. | 9 Electronics14 Jewellery28 Toys | Registered | 2024 |
| OUTDO 2152766 · TMA1188831 · design | XIAMEN MEGA KINGDOM TECHNOLOGY CO. LTD. | 9 Electronics | Registered | 2023 |
| OUADO 2128662 · TMA1208563 | an individual | 25 Clothing | Registered | 2023 |
| OUTDO 1439817 · TMA778409 · design | XIAMEN MEGA KINGDOM TECHNOLOGY CO. LTD. | 9 Electronics21 Housewares | Registered | 2010 |
| OYÉDO 1268549 · TMA764229 | an individual | 3 Cosmetics | Registered | 2010 |
| OHDIO 0926215 | Société Radio-Canada / Canadian Broadcasting Corporation | 1 Chemicals2 Paints3 Cosmetics+42 | Pending | 2020 |
| ODAYA 2212499 · TMA1223307 | AGENCE TINGG INC. | 4 Oils5 Pharmaceuticals10 Medical | Registered | 2024 |
| Otai 2211794 · TMA1243016 | Huizhou Outai Home Furnishing Co., Ltd. | 24 Textiles | Registered | 2024 |
| OTWD 2205719 · TMA1257868 · design | Off The Wall Displays Inc. | 11 Lighting20 Furniture | Registered | 2024 |
| ODEA 2188378 · TMA1232682 · design | ZHEJIANG ODEAR SPORTS GOODS CO.LTD | 28 Toys | Registered | 2024 |
| OIDEA 2181663 · TMA1229567 | OUTSTANDING IDEA LIMITED | 14 Jewellery | Registered | 2024 |
| ÖÖD 2173232 · TMA1256285 · design | an individual | 19 Building43 Restaurants | Registered | 2024 |
| OT 2167815 · TMA1277370 · design | OMNITRANS INC. | 16 Paper35 Advertising | Registered | 2024 |
| ODE 2131357 · TMA1223692 | Fellow Industries Inc. | 7 Machines | Registered | 2024 |
| OUTDEYA 2108470 · TMA1159427 | Mitsubishi Tanabe Pharma Corporation | 5 Pharmaceuticals | Registered | 2023 |
| OTHA 2106260 · TMA1176627 | 6594409 canada inc | 9 Electronics | Registered | 2023 |
| Oath 2087604 · TMA1170127 | HIGHBAR ENTERPRISES LTD. | 5 Pharmaceuticals | Registered | 2023 |
| ÖÖD 2084116 · TMA1247840 · design | an individual | 19 Building | Registered | 2024 |
| OTE 2081410 · TMA1174692 | OTE Household Appliances (Shenzhen) Co. Ltd | 7 Machines11 Lighting | Registered | 2023 |
| O8T 2077417 · TMA1204893 | Omniscient Neurotechnology Pty Limited | 9 Electronics42 Science | Registered | 2023 |