| OFFLINER 2104078 · TMA1208384 | Polaris Industries Inc. | 25 Clothing | Registered | 2023 |
| OFFLINX 1785032 · TMA1021612 | Moneris IP Holdings Inc. | 35 Advertising | Registered | 2019 |
| OVALIN 2238813 · TMA1258337 | an individual | 1 Chemicals | Registered | 2024 |
| OPULENCE 2156404 · TMA1282535 | LSI Industries Inc. | 11 Lighting | Registered | 2025 |
| OVLAIM 1989837 · TMA1136219 · design | an individual | 9 Electronics | Registered | 2022 |
| OBLUNGO 1973740 · TMA1278140 | Broan-NuTone LLC, a Delaware limited liability company | 11 Lighting | Registered | 2024 |
| OPULENCE 1971810 · TMA1255702 | an individual | 5 Pharmaceuticals | Registered | 2024 |
| OPLAND 1872842 · TMA1071860 · design | an individual | 32 Beer33 Wine43 Restaurants | Registered | 2020 |
| OPLAND 1872840 · TMA1085425 · design | an individual | 32 Beer33 Wine43 Restaurants | Registered | 2020 |
| OPLINK 1847324 · TMA1078400 | Oplink Communications US Division, LLC (a Texas limited liability company) | 9 Electronics | Registered | 2020 |
| OPLINK 1847323 · TMA1013226 | Oplink Communications US Division, LLC (a Texas limited liability company) | 9 Electronics | Registered | 2019 |
| OBLONE 1773354 · TMA1045623 | Owner not shown | 5 Pharmaceuticals10 Medical | Registered | 2019 |
| OPULENT 1742868 · TMA969764 | OPULENT TECHNO PTE. LTD. | 9 Electronics11 Lighting | Registered | 2017 |
| OPULENCE 1664825 · TMA907887 | Imperial Carpet & Home Inc. | 27 Carpets | Registered | 2015 |
| OPLINK 1661662 · TMA1104188 | Oplink Communications US Division, LLC (a Texas limited liability company) | 9 Electronics | Registered | 2021 |
| OPULENCE 1523375 · TMA839706 | Irving Paper Limited | 16 Paper | Registered | 2013 |
| OPULENT 1478190 · TMA822120 | Mesyl Limited | 3 Cosmetics | Registered | 2012 |
| OVALMATIC 1444731 · TMA771683 | Enterprises International, Inc. (a Washington corporation) | 7 Machines | Registered | 2010 |
| OPULENCE 1439525 · TMA770739 | Jewelex India Pvt. Ltd. | 14 Jewellery | Registered | 2010 |
| OPULENCE 1395449 · TMA766353 | SWIMC LLC | 2 Paints | Registered | 2010 |
| OPULENT 1373010 · TMA738844 | INTERCONTINENTAL PACKAGING CO. a Minnesota Corporation | 33 Wine | Registered | 2009 |
| OVALMATIC 1352698 · TMA724133 | Enterprises International, Inc. (a Washington corporation) | 6 Metal7 Machines22 Ropes | Registered | 2008 |
| OPALINE 1352165 · TMA783066 | Owner not shown | 11 Lighting | Registered | 2010 |
| OPULYN 1344925 · TMA778454 | Rohm and Haas Company | 1 Chemicals | Registered | 2010 |
| OPULENT 1320020 · TMA717707 · design | OPULENT TECHNO PTE. LTD. | 9 Electronics | Registered | 2008 |