| MASTERINJECT 1553236 · TMA904240 | an individual | 2 Paints | Registered | 2015 |
| MASTEREX 2077318 · TMA1157486 · design | an individual | 21 Housewares24 Textiles25 Clothing | Registered | 2022 |
| MASTERMIND 2067918 · TMA1135817 | Mastery Logistics Systems, Inc. | 42 Science | Registered | 2022 |
| MASTERFLEX 2007072 · TMA1141074 | ALLPRO CORPORATION | 16 Paper | Registered | 2022 |
| MASTERLINER 1771062 · TMA1030517 | GPCP IP Holdings LLC | 16 Paper | Registered | 2019 |
| MASTERING 1765479 · TMA1017111 | PEARSON EDUCATION, INC. | 9 Electronics41 Education42 Science | Registered | 2019 |
| MASTERLINE 1623336 · TMA890007 | ES OpCo USA LLC | 5 Pharmaceuticals7 Machines8 Hand+3 | Registered | 2014 |
| MASTERMADE 1477074 · TMA855039 | IW Apparel, LLC | 13 Firearms18 Leather25 Clothing+1 | Registered | 2013 |
| MASTERLINE 1300008 · TMA753125 | BEAULIEU GROUP, LLC | 27 Carpets | Registered | 2009 |
| MASTERMIND 1010294 · TMA725342 | MASTERMIND TOYS INC. | 35 Advertising | Registered | 2008 |
| MASTERMIND 0875302 · TMA612504 | HASBRO , INC., A RHODE ISLAND CORPORATION | 9 Electronics28 Toys | Registered | 2004 |
| MASTERMIND 0596468 · TMA349347 | MASTERMIND TOYS INC. | 35 Advertising37 Construction41 Education | Registered | 1988 |
| MASTERMIND 0449171 · TMA270675 | HASBRO , INC., A RHODE ISLAND CORPORATION | 28 Toys | Registered | 1982 |
| MASTERMIND 0412143 · TMA267720 | HASBRO , INC., A RHODE ISLAND CORPORATION | 28 Toys | Registered | 1982 |
| MASTERMIND 0412142 · TMA267719 · design | HASBRO , INC., A RHODE ISLAND CORPORATION | 28 Toys | Registered | 1982 |
| MASTERFLEX 0396465 · TMA221237 | Masterflex, LLC | 7 Machines17 Rubber | Registered | 1977 |
| MASTERMIND 2328422 | The Youth Effect Inc. | – | Pending | 2024 |
| MASTERFLEX 1983260 | Masterflex, LLC | 7 Machines9 Electronics17 Rubber | Pending | 2019 |
| MASTERPIECES 2147818 · TMA1186757 | The Upper Deck Company | 9 Electronics16 Paper35 Advertising+2 | Registered | 2023 |
| MASTERPIECES 2118290 · TMA1166084 | The Upper Deck Company | 9 Electronics16 Paper | Registered | 2023 |
| MASTERFINISH 1559185 · TMA894277 | Construction Research & Technology GmbH | 1 Chemicals | Registered | 2015 |
| MASTERPIECES 1380956 · TMA733519 | Hormel Foods Corporation | 29 Meat | Registered | 2009 |
| MASTERING360 2159524 | an individual | 41 Education | Pending | 2022 |
| MASTERLISE 2199165 · TMA1222519 · design | Kabushiki Kaisha Bandai Spirits(Bandai Spirits Co. Ltd.) | 28 Toys | Registered | 2024 |
| Mastermates 2181339 · TMA1230233 | 1749615 ONTARIO INC. | 10 Medical | Registered | 2024 |