| OMNIBULK 1422375 · TMA755347 | KEMIRA CHEMICALS, INC. | 1 Chemicals | Registered | 2009 |
| OMNIFILM 1110302 · TMA599194 | an individual | 5 Pharmaceuticals10 Medical | Registered | 2004 |
| OMNIFILM 0481632 · TMA279614 | Pliant, LLC | 16 Paper | Registered | 1983 |
| OMNIBLISS 2251313 · taste | Elevate Holdings, Inc. | 35 Advertising43 Restaurants | Pending | 2023 |
| OMNIBLU 2221035 | John Bean Technologies Corporation | 9 Electronics35 Advertising37 Construction+2 | Pending | 2022 |
| OMNIBLONDE 2003410 · TMA1119639 · design | Owner not shown | 3 Cosmetics21 Housewares | Registered | 2022 |
| OMNIPAL 2071809 · TMA1201221 | an individual | 9 Electronics | Registered | 2023 |
| OMNIPOLLO 1794684 · TMA1006201 · design | an individual | 16 Paper21 Housewares25 Clothing+1 | Registered | 2018 |
| OMNIPOLLO 1794671 · TMA1006200 | an individual | 16 Paper21 Housewares25 Clothing+1 | Registered | 2018 |
| OMNIPOL 1768201 · TMA977497 | an individual | 1 Chemicals | Registered | 2017 |
| OMNIBLANK 1445386 · TMA807954 | CORBIN MANUFACTURING, INC. d.b.a. SYSTEM SCIENCE INSTITUTE, a legal entity | 7 Machines8 Hand | Registered | 2011 |
| OMNIPL 2296307 | Hayward Industries, Inc. | 11 Lighting | Pending | 2023 |
| OMNIPL 2054846 | Hayward Industries, Inc. | 9 Electronics | Pending | 2020 |
| ONEFLOW 2236083 · TMA1256832 | Watts Regulator Co. | 1 Chemicals11 Lighting | Registered | 2024 |
| ONEBLADE 2232812 · TMA1243380 | an individual | 8 Hand | Registered | 2024 |
| ONEPULSE 2197785 · TMA1223224 | Startpulsing Limited | 35 Advertising42 Science | Registered | 2024 |
| ONEVALLEY 2143103 · TMA1185489 | OneValley, Inc. | 35 Advertising36 Finance41 Education+2 | Registered | 2023 |
| Onfleril 2141194 · TMA1193873 | MICROBIO CO. LTD. | 5 Pharmaceuticals | Registered | 2023 |
| ONEPLANET 2132654 · TMA1195832 · design | CS International Trading Inc. | 21 Housewares | Registered | 2023 |
| ONEPLUS 2126442 · TMA1221249 · design | OnePlus Technology (Shenzhen) Co. Ltd. | 18 Leather25 Clothing35 Advertising+3 | Registered | 2024 |
| OENOBIOL 2073693 · TMA1203832 | an individual | 3 Cosmetics5 Pharmaceuticals35 Advertising | Registered | 2023 |
| OMNYPULSE 2038265 · TMA1270723 | Biosense Webster, Inc. | 9 Electronics10 Medical | Registered | 2024 |
| OneFlock 2007254 · TMA1129134 | an individual | 45 Legal | Registered | 2022 |
| Omniflex 2004069 · TMA1129064 | Owner not shown | 17 Rubber20 Furniture | Registered | 2022 |
| Omblastys 1984622 · TMA1099091 | Y-mAbs Therapeutics, Inc | 5 Pharmaceuticals42 Science | Registered | 2021 |