| OUTSET 2154739 · TMA1191114 | Outset Medical, Inc. | 42 Science | Registered | 2023 |
| OUTSET 1863563 · TMA1087575 | 2572913 Ontario Inc. | 32 Beer33 Wine35 Advertising+1 | Registered | 2020 |
| OUTSET 1279434 · TMA684899 | FOX RUN USA, LLC | 21 Housewares | Registered | 2007 |
| Otacta 2353103 | Owner not listed | 9 Electronics35 Advertising42 Science | Pending | 2024 |
| OUTSET 2305932 | Owner not listed | 12 Vehicles | Pending | 2024 |
| OUTJUT 2286050 | an individual | 11 Lighting | Pending | 2023 |
| OUTWEST 2148720 · TMA1203123 · design | EJT Developments Inc | 12 Vehicles37 Construction | Registered | 2023 |
| OUTWEST 0875519 · TMA547150 · design | Excellent Eateries Inc. | 6 Metal9 Electronics14 Jewellery+14 | Registered | 2001 |
| OUTSIDER 2216578 · TMA1245451 | BATTLE CREEK EQUIPMENT CO. | 11 Lighting | Registered | 2024 |
| OUTSAD 2187327 · TMA1231634 | an individual | 3 Cosmetics18 Leather25 Clothing+1 | Registered | 2024 |
| ODCDEALS 2161474 · TMA1211176 | an individual | 20 Furniture21 Housewares22 Ropes | Registered | 2023 |
| OTTOSAT 2119004 · TMA1220392 | an individual | 9 Electronics | Registered | 2024 |
| OUTSTANDING 1995476 · TMA1125757 · design | OUTSTANDING STEM STUDY LTD. | 41 Education | Registered | 2022 |
| OTOSTICK 1786516 · TMA979869 · design | an individual | 10 Medical | Registered | 2017 |
| otostick 1786065 · TMA979868 | an individual | 10 Medical | Registered | 2017 |
| OUTCIDER 1740813 · TMA1000701 | Bacardi & Company Limited | 32 Beer33 Wine | Registered | 2018 |
| Outsider 1738582 · TMA980001 | ROSKI COMPOSITES INC. | 12 Vehicles | Registered | 2017 |
| ODACITÉ 1692906 · TMA923040 · design | Odacite Inc. | 3 Cosmetics | Registered | 2015 |
| OUTSIDEIQ 1687705 · TMA954719 | EXIGER CANADA, INC. | 35 Advertising36 Finance42 Science | Registered | 2016 |
| ODACITÉ 1682060 · TMA951871 · design | DÉVELOPPEMENTS ODACITÉ INC. | 35 Advertising36 Finance37 Construction | Registered | 2016 |
| ODACITÉ 1681955 · TMA951857 | DÉVELOPPEMENTS ODACITÉ INC. | 35 Advertising36 Finance37 Construction | Registered | 2016 |
| OTAKUTHON 1608955 · TMA922483 | an individual | 35 Advertising41 Education | Registered | 2015 |
| OATSTANDING 1566321 · TMA859477 | Sneaky Pete's Beverage, LLC | 30 Coffee32 Beer | Registered | 2013 |
| OUTSTANDING 1497706 · TMA862101 | an individual | 6 Metal9 Electronics12 Vehicles+13 | Registered | 2013 |
| OATSTANDING 1355557 · TMA766764 | Victoria's Secret Stores Brand Management, LLC | 3 Cosmetics | Registered | 2010 |