| OptiST 2129294 · TMA1250792 | an individual | 9 Electronics | Registered | 2024 |
| OPTESSA 1314469 · TMA710154 | OPTESSA INC. | 9 Electronics42 Science | Registered | 2008 |
| OPTEASE 1160248 · TMA655124 | Cardinal Health 529, LLC | 10 Medical | Registered | 2005 |
| OPTISET 0814765 · TMA478848 | Sanofi-Aventis Deutschland GmbH | 10 Medical | Registered | 1997 |
| OPTISET 0554358 · TMA338346 | AKZO NOBEL COATINGS INC. | 1 Chemicals2 Paints7 Machines | Registered | 1988 |
| OPTEJET 2212691 | Eyenovia, Inc. | 5 Pharmaceuticals10 Medical | Pending | 2022 |
| OPTEQ 2026263 · TMA1265124 · design | MAYTRONICS LTD. | 7 Machines | Registered | 2024 |
| OPTEQ 2026255 · TMA1265123 | MAYTRONICS LTD. | 7 Machines | Registered | 2024 |
| OpTEAsoft 2004155 · TMA1138437 | SuperGrid Institute | 9 Electronics42 Science | Registered | 2022 |
| OPTEX 1815845 · TMA1097553 · design | Optex Co. Ltd. | 7 Machines9 Electronics12 Vehicles+1 | Registered | 2021 |
| OPTEGO 1795857 · TMA992799 | an individual | 9 Electronics10 Medical | Registered | 2018 |
| OPTIS 1615295 · TMA912510 | LightLab Imaging, Inc. | 9 Electronics10 Medical | Registered | 2015 |
| OPTECH 1430377 · TMA767788 | TELEDYNE DIGITAL IMAGING, INC. | 9 Electronics42 Science | Registered | 2010 |
| OPTOS 1326192 · TMA730566 | TK Canada Limited | 20 Furniture | Registered | 2008 |
| OPTEC 1212853 · TMA660387 | GCP Applied Technologies Inc. | 1 Chemicals | Registered | 2006 |
| OPTECH 1169714 · TMA672770 | PPG Industries Ohio, Inc. (a Delaware corporation) | 2 Paints | Registered | 2006 |
| OPTOS 1084474 · TMA586932 | OPTOS PLC | 9 Electronics10 Medical42 Science+1 | Registered | 2003 |
| OPTIS 1076418 · TMA617971 · design | an individual | 9 Electronics42 Science | Registered | 2004 |
| OPTIS 1076179 · TMA617306 | an individual | 9 Electronics42 Science | Registered | 2004 |
| OPTEX 1034403 · TMA555269 · design | GENTEC, a partnership consisting of 901089 Ontario Limited and 2494979 Ontario Limited | 7 Machines9 Electronics16 Paper+3 | Registered | 2001 |
| OPTEX 0490255 · TMA281490 · design | GENTEC, a partnership consisting of 901089 Ontario Limited and 2494979 Ontario Limited | 6 Metal9 Electronics18 Leather+1 | Registered | 1983 |
| OPTECH 0471213 · TMA287786 · design | an individual | 9 Electronics | Registered | 1984 |
| OPTEX 0461624 · TMA277957 | GENTEC, a partnership consisting of 901089 Ontario Limited and 2494979 Ontario Limited | 6 Metal7 Machines9 Electronics+7 | Registered | 1983 |
| OPTEX 0425067 · TMA269890 | GENTEC, a partnership consisting of 901089 Ontario Limited and 2494979 Ontario Limited | 3 Cosmetics6 Metal7 Machines+11 | Registered | 1982 |
| Optish 2371879 | Zhangjiagang Fengniao E-commerce Co. Ltd. | 6 Metal | Pending | 2024 |