| XENTARI 2230550 · TMA1245661 | Valent BioSciences LLC | 5 Pharmaceuticals | Registered | 2024 |
| XENTARI 2060027 · TMA1116413 | Valent BioSciences LLC | 5 Pharmaceuticals | Registered | 2021 |
| XENTRON 0893829 · TMA582457 | an individual | 9 Electronics11 Lighting | Registered | 2003 |
| XENITRON 2071663 · TMA1205863 | EQUUS UK TOPCO LTD | 1 Chemicals | Registered | 2023 |
| XCENTRIC 1095634 · TMA592375 | Procter & Gamble International Operations SA | 3 Cosmetics | Registered | 2003 |
| XCENTRIC 2369757 | PENTAIR FLOW TECHNOLOGIES, LLC | 7 Machines | Pending | 2024 |
| XANTREX 0875397 · TMA540751 | XANTREX LLC | 9 Electronics11 Lighting | Registered | 2001 |
| XIMITRY 2256865 | Owner not listed | 9 Electronics10 Medical42 Science | Pending | 2023 |
| XENTROVIA 1889899 · TMA1089451 | ViiV Healthcare UK (No.4) Limited | 5 Pharmaceuticals | Registered | 2020 |
| XENMATRIX 1447279 · TMA856201 | C.R. BARD, INC. A LEGAL ENTITY | 5 Pharmaceuticals | Registered | 2013 |
| XenithIR 2071744 · TMA1193341 | Saint-Gobain Innovative Materials Belgium SA | 17 Rubber | Registered | 2023 |
| XANTREME 1933422 · TMA1123401 | an individual | 1 Chemicals | Registered | 2022 |
| XANDR 1920988 · TMA1126667 · design | Owner not shown | 9 Electronics35 Advertising42 Science | Registered | 2022 |
| XANDR 1920986 · TMA1126666 | Owner not shown | 9 Electronics35 Advertising42 Science | Registered | 2022 |
| Xander 1914241 · TMA1113363 | an individual | 41 Education | Registered | 2021 |
| XEMDRO 1812517 · TMA1069028 | Cipla USA, Inc. | 5 Pharmaceuticals | Registered | 2020 |
| XANDER 1808610 · TMA1053766 | Delta Faucet Company | 11 Lighting | Registered | 2019 |
| XIAMETER 1451888 · TMA773947 · design | DOW CORNING CORPORATION | 1 Chemicals2 Paints3 Cosmetics+4 | Registered | 2010 |
| XIAMETER 1451887 · TMA776199 · design | DOW CORNING CORPORATION | 1 Chemicals2 Paints3 Cosmetics+4 | Registered | 2010 |
| XIAMETER 1123222 · TMA594940 | DOW CORNING CORPORATION | 1 Chemicals2 Paints3 Cosmetics+4 | Registered | 2003 |
| XENDRIVE 0895250 · TMA582338 | an individual | 9 Electronics11 Lighting | Registered | 2003 |
| XCOUNTER 0886594 · TMA565803 | XEROX CORPORATION | 9 Electronics | Registered | 2002 |
| Xantur 0881670 · TMA529881 | Igepa group GmbH & Co. KG | 16 Paper | Registered | 2000 |
| XANTURAL 0868153 · TMA565686 | CP KELCO U.S., INC. | 1 Chemicals | Registered | 2002 |
| XANDRES 0846879 · TMA502096 | Xandres | 18 Leather24 Textiles25 Clothing | Registered | 1998 |