| CylanceGUARD 2199503 | Cylance Inc. | 42 Science | Pending | 2022 |
| CylanceGATEWAY 2209805 · TMA1224662 | Cylance Inc. | 9 Electronics42 Science | Registered | 2024 |
| CYLANCEPROTECT 1771573 · TMA983192 | Cylance Inc. | 9 Electronics | Registered | 2017 |
| CLEANCOVER 1973622 · TMA1199611 | Broan-NuTone LLC, a Delaware limited liability company | 11 Lighting | Registered | 2023 |
| CYLANCE 1758154 · TMA957656 · design | Cylance Inc. | 9 Electronics42 Science | Registered | 2016 |
| CYLANCE 1601126 · TMA919113 | Cylance Inc. | 9 Electronics42 Science | Registered | 2015 |
| CLEANCART 0864456 · TMA515446 | an individual | 5 Pharmaceuticals10 Medical | Registered | 1999 |
| CLAIMSALERT 0859516 · TMA515125 | Crawford & Company | 35 Advertising36 Finance38 Telecommunications | Registered | 1999 |
| CylancePERSONA 2209806 · TMA1224663 | Cylance Inc. | 9 Electronics42 Science | Registered | 2024 |
| CYLANCEOPTICS 2199501 | Cylance Inc. | 9 Electronics42 Science | Pending | 2022 |
| CLAYMAKER 2262002 · TMA1281338 | CLAYNOSAURZ INC. | 28 Toys | Registered | 2025 |
| CLAYMAKER 2262000 · TMA1281337 | CLAYNOSAURZ INC. | 9 Electronics35 Advertising41 Education+1 | Registered | 2025 |
| CLINCHER 2225755 · TMA1251233 | NORD GEAR LIMITED/ENGRENAGES NORD LIMITEE | 7 Machines | Registered | 2024 |
| CLINCARD 2080447 · TMA1141469 · design | Greenphire, LLC | 9 Electronics36 Finance42 Science | Registered | 2022 |
| CLEANCURVE 2034335 · TMA1269469 | AS America, Inc. | 11 Lighting | Registered | 2024 |
| CLINCARD 1971649 · TMA1138094 | Greenphire, Inc. | 9 Electronics36 Finance42 Science | Registered | 2022 |
| CLAMCASE 1712209 · TMA947968 · design | Incipio, LLC | 9 Electronics35 Advertising | Registered | 2016 |
| CLAMCASE 1683713 · TMA922967 | Incipio, LLC | 9 Electronics | Registered | 2015 |
| CLEANCARE 1653883 · TMA904527 | Kimberly-Clark Worldwide, Inc. | 16 Paper | Registered | 2015 |
| CLINICSERVER 1542582 · TMA832421 | IBL - INTERNET BUSINESS LOGIC INC. | 9 Electronics | Registered | 2012 |
| CLEANSESMART 1495389 · TMA845405 | The Clorox Company of Canada Ltd. | 5 Pharmaceuticals | Registered | 2013 |
| CLEANSTART 1420979 · TMA763387 | CANADIAN STANDARDS ASSOCIATION | 16 Paper41 Education42 Science | Registered | 2010 |
| ClinicaVR 1360315 · TMA763021 | Digital MediaWorks Inc. | 9 Electronics | Registered | 2010 |
| CLEANSTART 1325967 · TMA699700 | Nufarm Agriculture Inc. | 5 Pharmaceuticals | Registered | 2007 |
| CLENCHER 1234764 · TMA698152 | HUBBELL INCORPORATED | 9 Electronics | Registered | 2007 |