| ONECELL 1899601 · TMA1103704 | CommScope Technologies LLC | 9 Electronics | Registered | 2021 |
| ONCALL 1142259 · TMA607218 | Valsoft | 9 Electronics | Registered | 2004 |
| ONECELL 2134968 | Implant Therapeutics Inc. | 1 Chemicals5 Pharmaceuticals | Pending | 2021 |
| ONCALL 2108670 | Oncall Health Inc. | 9 Electronics42 Science | Pending | 2021 |
| OmniGLYZOR 2229893 · TMA1245649 | an individual | 1 Chemicals5 Pharmaceuticals | Registered | 2024 |
| ONIGAL 2131264 · TMA1193766 · design | Shenzhen Zhongxin Jiahe Electronic Technology Development Co.Ltd | 9 Electronics35 Advertising | Registered | 2023 |
| Onglory 2099357 · TMA1175790 | an individual | 11 Lighting | Registered | 2023 |
| oneisall 2080027 · TMA1165923 | Shenzhen Shouzheng Chuqi Electronic Commerce Co. Ltd. | 8 Hand | Registered | 2023 |
| ONECLICKUPSELL 2059123 · TMA1131243 | Zipify, LLC | 42 Science | Registered | 2022 |
| Omegle 2045513 · TMA1124496 | OMEGLE.COM LLC | 38 Telecommunications | Registered | 2022 |
| OMEGALIF 1980790 · TMA1245957 | Spinal Elements, Inc. | 10 Medical | Registered | 2024 |
| ONE2CLICK 1980401 · TMA1156888 | ENGINEERED FLOORS, LLC | 19 Building | Registered | 2022 |
| ONESEAL 1947503 · TMA1206844 | an individual | 6 Metal | Registered | 2023 |
| ONEGOLD 1916991 · TMA1093816 | ONEGOLD Inc. | 36 Finance | Registered | 2021 |
| ONECAL 1892035 · TMA1098593 | Fluke Corporation | 9 Electronics42 Science | Registered | 2021 |
| ONESOLUTION 1880594 · TMA1078238 | Owner not shown | 44 Medical | Registered | 2020 |
| ONKALO 1872570 · TMA1087150 | an individual | 6 Metal7 Machines9 Electronics+7 | Registered | 2020 |
| ONESEAL 1865711 · TMA1090391 | Tremco CPG Inc. | 2 Paints | Registered | 2020 |
| ONQUELVA 1852540 · TMA1071484 · design | Daiichi Sankyo Company, Limited | 5 Pharmaceuticals | Registered | 2020 |
| ONECLICK 1827013 · TMA1037708 | Oneclick License, LLC | 9 Electronics12 Vehicles14 Jewellery+3 | Registered | 2019 |
| ONECLICK 1822304 · TMA1037755 | Oneclick License, LLC | 37 Construction42 Science | Registered | 2019 |
| ONCALL4ON 1805287 · TMA1059550 | an individual | 9 Electronics14 Jewellery16 Paper+6 | Registered | 2019 |
| OMNICLICK 1774842 · TMA1051591 | an individual | 5 Pharmaceuticals9 Electronics10 Medical | Registered | 2019 |
| OMNICLASS 1726820 · TMA924239 | HONEYWELL INTERNATIONAL INC. | 9 Electronics | Registered | 2015 |
| ONCALERT 1726286 · TMA1058356 | Vigilant Biosciences, Inc. | 5 Pharmaceuticals42 Science44 Medical | Registered | 2019 |