| ombar 1912045 · TMA1120719 | Mood Foods Ltd | 29 Meat30 Coffee35 Advertising | Registered | 2022 |
| OneBrain 2300248 · TMA1229113 | Minnetronix Neuro, Inc. | 9 Electronics42 Science | Registered | 2024 |
| ONEFIRE 2173679 · TMA1225306 | Guangzhou Tuoke Trading Co. Ltd. | 9 Electronics11 Lighting | Registered | 2024 |
| Oumefar 2076154 · TMA1155409 | SHENZHEN CHUJIN NETWORK TECHNOLOGY CO.LTD | 7 Machines | Registered | 2022 |
| ONPHARM 1687160 · TMA920457 | OnPharm Inc. | 35 Advertising44 Medical | Registered | 2015 |
| ONBOARD 1558809 · TMA879863 · design | McGraw Hill LLC | 41 Education | Registered | 2014 |
| OHMBARS 1535886 · TMA902096 · design | Ohmbars Inc. | 30 Coffee | Registered | 2015 |
| OMNIBER 1010290 · TMA602415 | Agilent Technologies, Inc. (a Delaware corporation) | 7 Machines9 Electronics12 Vehicles+4 | Registered | 2004 |
| ONBOARD 2360394 · design | Marcamp Foods LLC | 29 Meat | Pending | 2024 |
| OnePort 2281286 | FIDALIA NETWORKS INC. | 38 Telecommunications | Pending | 2023 |
| ONBOARD 2270121 | Marcamp Foods LLC | 29 Meat43 Restaurants | Pending | 2023 |
| ONBOARD 2253137 | Owner not listed | 42 Science | Pending | 2023 |
| ONBOARD 0922439 | British Columbia Ferry Services Inc. | 1 Chemicals2 Paints3 Cosmetics+42 | Pending | 2013 |
| ONEBERRIE 2351043 | Owner not listed | 24 Textiles25 Clothing | Pending | 2024 |
| OneBrock 2248946 · TMA1257067 | CTB, INC. | 35 Advertising | Registered | 2024 |
| Ombriatech 2237319 · TMA1256952 | Ombriati Corp. | 9 Electronics | Registered | 2024 |
| ONEPRINT 2230900 · TMA1247194 | LEXMARK INTERNATIONAL, INC. | 2 Paints35 Advertising | Registered | 2024 |
| OMBRAE 2182932 · TMA1230378 · design | Ombrae Studios Inc. | 6 Metal42 Science | Registered | 2024 |
| OMBRAE 2182931 · TMA1230377 | Ombrae Studios Inc. | 6 Metal42 Science | Registered | 2024 |
| onebright 2170138 · TMA1221433 | ONEBRIGHT BIDCO LIMITED | 9 Electronics42 Science | Registered | 2024 |
| OMBRA 2148304 · TMA1225199 | DEL FRESCO PRODUCE LTD. | 31 Fresh | Registered | 2024 |
| Ombear 2137549 · TMA1198988 | 9447-7759 Québec inc. | 30 Coffee | Registered | 2023 |
| onebright 2125036 · TMA1216191 | ONEBRIGHT BIDCO LIMITED | 41 Education42 Science44 Medical | Registered | 2023 |
| OMNIPRESENT 2110515 · TMA1189608 · design | Omipresent Group Limited | 35 Advertising42 Science | Registered | 2023 |
| OMIBRO 2106578 · TMA1232076 · design | Zhenshi Information Technology (Shanghai) Company Limited | 9 Electronics14 Jewellery25 Clothing+2 | Registered | 2024 |