| OKSTENCK 2233346 · TMA1256640 | Ningbo Huahongzhengte Information Technology Co. Ltd | 18 Leather | Registered | 2024 |
| Octomo 2223798 · TMA1248891 | Shenzhen Aokeduomo Technology Co., Ltd. | 12 Vehicles | Registered | 2024 |
| OAKTEN 2221685 · TMA1248592 | an individual | 7 Machines | Registered | 2024 |
| OSTENE 2210774 · TMA1271204 | BAXTER INTERNATIONAL INC. | 5 Pharmaceuticals | Registered | 2024 |
| OSTENIL 2209946 · TMA1280861 | TRB CHEMEDICA SA | 5 Pharmaceuticals | Registered | 2025 |
| OCTANE 2177613 · TMA1259456 | OTOY, Inc. | 9 Electronics42 Science | Registered | 2024 |
| Ocatoma 2156655 · TMA1208754 | Shenzhen Xingzhiyuan Technology Co. Ltd. | 25 Clothing | Registered | 2023 |
| OCTANE 2110124 · TMA1180549 · design | Octane Systems Canada Corp. | 9 Electronics42 Science | Registered | 2023 |
| Octamber 2087515 · TMA1176463 | Dongguan Hongjing Mould Co. Ltd. | 14 Jewellery | Registered | 2023 |
| OZYTINI 2087136 · TMA1170114 | BOEHRINGER INGELHEIM INTERNATIONAL GMBH | 5 Pharmaceuticals | Registered | 2023 |
| OSSTEM 2062021 · TMA1207053 | OSSTEM IMPLANT CO., LTD | 5 Pharmaceuticals10 Medical | Registered | 2023 |
| OSTUNE 2033345 · TMA1213921 | OSRAM GmbH | 9 Electronics11 Lighting | Registered | 2023 |
| OCTANE 1948224 · TMA1182255 | Octane Systems Canada Corp. | 9 Electronics35 Advertising42 Science | Registered | 2023 |
| OQTYMPO 1901844 · TMA1089317 | Midatech Pharma (Wales) Limited | 5 Pharmaceuticals | Registered | 2020 |
| OCTANE 1852618 · TMA1081010 | an individual | 7 Machines9 Electronics16 Paper | Registered | 2020 |
| OSTENT 1799976 · TMA993949 · design | Shenzhen Ostent Technology Co. Ltd. | 28 Toys | Registered | 2018 |
| OsteoMAP 1781134 · TMA976290 | Warsaw Orthopedic Inc. | 44 Medical | Registered | 2017 |
| OCTANE 1735617 · TMA979180 | Vicimus Inc. | 9 Electronics42 Science | Registered | 2017 |
| OSTEOAMP 1735230 · TMA993040 | Bioventus LLC | 5 Pharmaceuticals | Registered | 2018 |
| OSTEOAMP 1735229 · TMA993042 · design | Bioventus LLC | 5 Pharmaceuticals | Registered | 2018 |
| OXTENDA 1684885 · TMA944170 | INTELLIPHARMACEUTICS CORP. | 5 Pharmaceuticals42 Science | Registered | 2016 |
| OCTOMORE 1597325 · TMA878809 | BRUICHLADDlCH DISTILLERY COMPANY LIMITED | 33 Wine | Registered | 2014 |
| OCTANE 1594796 · TMA855769 | Polaris Industries Inc. | 12 Vehicles | Registered | 2013 |
| OCTEON 1576474 · TMA860370 | Marvell Asia Pte, Ltd. | 9 Electronics | Registered | 2013 |
| OCTANE 1518489 · TMA839786 | Choice Spine, LLC | 10 Medical | Registered | 2013 |