| CLOZY 1900320 · TMA1098911 | Mary Import inc. | 25 Clothing | Registered | 2021 |
| CLOSE 1056730 · TMA616279 | GAP (ITM) INC. | 3 Cosmetics | Registered | 2004 |
| CLOYES 0545471 · TMA319826 | HH-Cloyes, Inc. | 7 Machines | Registered | 1986 |
| CLOCHE 2046634 | VYDL Inc. | 6 Metal9 Electronics16 Paper+7 | Pending | 2020 |
| COLOSSE 2254204 · TMA1283013 · design | 9394-4049 Québec Inc. f.a.s.n.r.s. COLOSSE FUMOIR / COLOSSE SMOKEHOUSE | 29 Meat30 Coffee35 Advertising+1 | Registered | 2025 |
| COOLEES 1635980 · TMA944371 | Handi-Craft Company | 10 Medical | Registered | 2016 |
| COLISÉE 0747023 · TMA457719 | RICHEMONT INTERNATIONAL SA | 14 Jewellery | Registered | 1996 |
| CLOOZZ 2159845 · TMA1265339 | an individual | 9 Electronics14 Jewellery35 Advertising | Registered | 2024 |
| clougg 2112668 · TMA1180646 | an individual | 16 Paper | Registered | 2023 |
| CLOC 2098263 · TMA1187418 | Shenzhen Skinod Technology Co.Ltd. | 10 Medical | Registered | 2023 |
| CLOAK 1991079 · TMA1224836 | DERMA RESEARCH GROUP INC. | 3 Cosmetics | Registered | 2024 |
| CLUSE 1851695 · TMA1050287 · design | Owner not shown | 9 Electronics14 Jewellery18 Leather | Registered | 2019 |
| Cliché 1830999 · TMA1003628 | Vineland Estates Winery Ltd. | 21 Housewares33 Wine | Registered | 2018 |
| ColLaZeo 1806197 · TMA1031437 | an individual | 3 Cosmetics | Registered | 2019 |
| CLUSE 1779492 · TMA972583 · design | Owner not shown | 9 Electronics14 Jewellery | Registered | 2017 |
| CLUSE 1779487 · TMA972591 | Owner not shown | 9 Electronics14 Jewellery | Registered | 2017 |
| CHOLEEZE 1657633 · TMA958635 | GELDA SCIENTIFIC AND INDUSTRIAL DEVELOPMENT CORPORATION | 5 Pharmaceuticals | Registered | 2016 |
| COLOSSEO 1634968 · TMA938399 | Oldcastle Building Products Canada, Inc./Les Matériaux de Construction Oldcastle Canada, Inc. | 19 Building | Registered | 2016 |
| CLOGAU 1622883 · TMA903602 | Clogau Gold of Wales Ltd | 14 Jewellery | Registered | 2015 |
| CLOX 1588360 · TMA857994 | Rodair Holdings Ltd. | 20 Furniture | Registered | 2013 |
| CLUES 1496129 · TMA822837 | an individual | 9 Electronics14 Jewellery16 Paper+6 | Registered | 2012 |
| CLIQUE 1469916 · TMA794399 | Summit Resort Management Inc. | 37 Construction41 Education43 Restaurants | Registered | 2011 |
| CLEK 1371664 · TMA784474 | Clek Inc. | 12 Vehicles18 Leather | Registered | 2010 |
| CLASSE 1213516 · TMA642332 · design | Sound United, LLC | 9 Electronics37 Construction | Registered | 2005 |
| CLASSÉ 1213515 · TMA641798 | Sound United, LLC | 9 Electronics37 Construction | Registered | 2005 |