| ORTHOPAK 0525461 · TMA308924 | EBI, LLC | 10 Medical | Registered | 1985 |
| OrthoPure 2223126 · TMA1248793 | NAKA HERBS & VITAMINS LTD. | 5 Pharmaceuticals | Registered | 2024 |
| ORTHOVANT 1941572 · TMA1137926 | Roivant Sciences GmbH | 5 Pharmaceuticals42 Science44 Medical | Registered | 2022 |
| ORTHOPULSE 1689398 · TMA928068 | LLLT Technologies SA, a Swiss Corporation | 10 Medical | Registered | 2016 |
| ORTHOPHASE 2325616 | Orthophase Industrial Limited | 9 Electronics41 Education42 Science | Pending | 2024 |
| OrthoPrax 2175995 · TMA1248079 | an individual | 10 Medical25 Clothing28 Toys+1 | Registered | 2024 |
| ORTHOVILLE 1774662 · TMA963638 · design | Orthodontiste Orthoville Inc. | 44 Medical | Registered | 2017 |
| ORTHOAPNEA 1707942 · TMA927796 · design | an individual | 10 Medical | Registered | 2016 |
| ORTOPÉ 1698234 · TMA995389 · design | an individual | 25 Clothing | Registered | 2018 |
| ORTHOPLAY 1642393 · TMA983112 | an individual | 9 Electronics42 Science | Registered | 2017 |
| ORTHOPHIA 1545700 · TMA832195 | TOKUYAMA CORPORATION | 5 Pharmaceuticals | Registered | 2012 |
| orthoplast 1395324 · TMA747212 | National Shoe Specialties Limited | 17 Rubber | Registered | 2009 |
| ORTHOPLAST 1393402 · TMA756651 | Owner not shown | 17 Rubber | Registered | 2010 |
| ORTHOPRO 1257866 · TMA716534 | JMBH Holdings, LLC | 10 Medical | Registered | 2008 |
| ORTHOFAB 1238358 · TMA650765 | ORTHOFAB INC. | 12 Vehicles35 Advertising39 Transport+1 | Registered | 2005 |
| ORTOPAD 1058162 · TMA566119 | an individual | 3 Cosmetics | Registered | 2002 |
| ORTHOPRIM 0864382 · TMA513640 | an individual | 10 Medical | Registered | 1999 |
| ORTHOPLAST 0158138 · TMDA57297 | Performance Health Holdings, Inc. | 10 Medical | Registered | 1933 |
| ORTHOPOD 2302982 | an individual | 9 Electronics | Pending | 2023 |
| ORTHOVAC 1960568 | ConMed Corporation | 10 Medical | Pending | 2019 |
| OrthoBreathe 2197354 · TMA1237381 | Alinnovate Health and Safety Applications Inc. | 5 Pharmaceuticals | Registered | 2024 |
| OrthoBreathe 2315905 | Alinnovate Health and Safety Applications Inc. | 10 Medical | Pending | 2024 |
| ORTHOBRIDGE 1746830 · TMA1045126 | Footbridge Centre for Integrated Foot & Ankle Care Inc. | 5 Pharmaceuticals8 Hand9 Electronics+5 | Registered | 2019 |
| ORTHOEVIDENCE 1530096 · TMA834321 | ORTHOEVIDENCE INC. | 9 Electronics16 Paper35 Advertising+1 | Registered | 2012 |
| Orrdiffi 2239545 · TMA1258401 | an individual | 21 Housewares | Registered | 2024 |