| OWL 2246780 · TMA1267129 · design | HONGKONG NYX TECHNOLOGY LIMITED | 28 Toys | Registered | 2024 |
| OOLY 2006468 · TMA1108315 | OOLY, LLC. | 16 Paper28 Toys | Registered | 2021 |
| OWL 1975249 · TMA1255717 | KAJI CORPORATION, a legal entity | 10 Medical12 Vehicles20 Furniture | Registered | 2024 |
| OWL 1965738 · TMA1198329 | Owl Labs, Inc. | 9 Electronics | Registered | 2023 |
| OWL 1964948 · TMA1198328 | Owl Labs, Inc. | 9 Electronics | Registered | 2023 |
| OWL 1881398 · TMA1263493 | an individual | 9 Electronics41 Education | Registered | 2024 |
| OOLY 1844160 · TMA1088988 · design | OOLY, LLC. | 9 Electronics16 Paper35 Advertising | Registered | 2020 |
| OWL 1753839 · TMA955394 | OWL Orphaned Wildlife Rehabilitation Society | 35 Advertising36 Finance39 Transport+4 | Registered | 2016 |
| OLLY 1718522 · TMA1052900 · design | an individual | 5 Pharmaceuticals | Registered | 2019 |
| OLLY 1718520 · TMA1052902 · design | an individual | 5 Pharmaceuticals | Registered | 2019 |
| OLLY 1681907 · TMA1026591 | an individual | 5 Pharmaceuticals | Registered | 2019 |
| OWL 1145061 · TMA656037 | Teranet Inc. | 35 Advertising36 Finance42 Science+1 | Registered | 2006 |
| OLLY 1105105 · TMA586926 | OS Debt Holders Investment Fund, LLC | 2 Paints3 Cosmetics5 Pharmaceuticals+7 | Registered | 2003 |
| OWL 0839377 · TMA498094 · design | JACOBS DOUWE EGBERTS RTL OWL SG PTE. LTD. | 30 Coffee | Registered | 1998 |
| OWL 0584104 · TMA382178 | Bayard Presse Canada Inc. | 9 Electronics16 Paper25 Clothing+4 | Registered | 1991 |
| OWL 0473258 · TMA303607 · design | OWL RAFTING INC. | 41 Education | Registered | 1985 |
| OWL 0166735 · UCA5063 | Scandinavian Tobacco Group Canada Inc. | 29 Meat30 Coffee34 Tobacco | Registered | 1935 |
| OWL 2281257 | Hummingbird Sport Limited Partnership | 18 Leather21 Housewares25 Clothing+1 | Pending | 2023 |
| OLY 2209730 | Olyseum SA | 35 Advertising36 Finance38 Telecommunications+2 | Pending | 2022 |
| OWLEYE 2296449 · design | OwlEye Cybersecurity Inc. | 35 Advertising42 Science45 Legal | Pending | 2023 |
| OWLEYE 2296448 | OwlEye Cybersecurity Inc. | 35 Advertising42 Science45 Legal | Pending | 2023 |
| owlyee 2269850 | an individual | 21 Housewares | Pending | 2023 |
| OWALA 2023963 · TMA1135674 | Runway Blue, LLC. | 9 Electronics18 Leather21 Housewares+1 | Registered | 2022 |
| OILLY 1689829 · TMA916799 · design | Parts Avatar Investments Inc. | 12 Vehicles35 Advertising | Registered | 2015 |
| OLWAY 2374388 | 16517692 Canada Inc. | 5 Pharmaceuticals21 Housewares25 Clothing+3 | Pending | 2025 |