| OST 2191468 · TMA1241210 · design | an individual | 5 Pharmaceuticals10 Medical44 Medical | Registered | 2024 |
| OKTA 2154759 · TMA1191118 · design | YIWU MUGUO BAGS CO. LTD. | 18 Leather | Registered | 2023 |
| OHST 1903349 · TMA1105786 · design | Board of Certified Safety Professionals, Inc. | 42 Science | Registered | 2021 |
| OUST 1823807 · TMA1018165 | OCuSOFT, Inc. a legal entity | 5 Pharmaceuticals | Registered | 2019 |
| OKTA 1763142 · TMA958458 | Okta, Inc. | 9 Electronics42 Science45 Legal | Registered | 2016 |
| OCTA 1719818 · TMA1019902 | Teijin Frontier Co. Ltd. | 23 Yarns24 Textiles25 Clothing | Registered | 2019 |
| OCATA 1716992 · TMA1032595 | ASTELLAS INSTITUTE FOR REGENERATIVE MEDICINE | 5 Pharmaceuticals42 Science | Registered | 2019 |
| OST 1684501 · TMA971028 | Spectrum Tracer Services, LLC | 42 Science | Registered | 2017 |
| OUST 1359092 · TMA724266 | S.C. Johnson & Son, Inc. | 4 Oils | Registered | 2008 |
| OST 1282639 · TMA686030 | Platinum Naturals Ltd. | 5 Pharmaceuticals | Registered | 2007 |
| OUST 0469832 · TMA282431 | Discovery Purchaser Corporation | 5 Pharmaceuticals | Registered | 1983 |
| OCTA 2326230 · design | an individual | 7 Machines35 Advertising42 Science | Pending | 2024 |
| OKTA 2265261 · design | Okta, Inc. | 9 Electronics36 Finance41 Education+1 | Pending | 2023 |
| OUST 2067622 · design | an individual | 12 Vehicles22 Ropes | Pending | 2020 |
| OST 2006273 | The Ontario Association of Osteopathic Manual Practitioners | 44 Medical | Pending | 2020 |
| OKKTO 2245304 · TMA1264405 | CANDEREL MANAGEMENT INC. | 35 Advertising36 Finance37 Construction+4 | Registered | 2024 |
| OESD 2192972 · TMA1219386 | Oklahoma Embroidery Supply & Design, LLC | 8 Hand9 Electronics23 Yarns+3 | Registered | 2024 |
| OGYTUHI 2183365 · TMA1231297 | Dongguan Youjia Trading Co. Ltd. | 22 Ropes | Registered | 2024 |
| OUSIDE 2150242 · TMA1217303 | Shenzhen OuSiDe Technology Co. Ltd | 9 Electronics11 Lighting | Registered | 2024 |
| Oashot 2149229 · TMA1203145 | an individual | 28 Toys | Registered | 2023 |
| OYESAUTO 2134907 · TMA1214189 | Shenzhen Oyes Technology Co. Ltd | 21 Housewares | Registered | 2023 |
| OKAYD 2118203 · TMA1162743 | Proof Label Services LLC | 35 Advertising42 Science45 Legal | Registered | 2023 |
| OZAWADE 2113139 · TMA1160529 | BIOPROJET EUROPE LIMITED | 5 Pharmaceuticals | Registered | 2023 |
| OCTO 2100398 · TMA1171458 | an individual | 9 Electronics36 Finance38 Telecommunications+3 | Registered | 2023 |
| OKEDI 2089277 · TMA1211771 | an individual | 5 Pharmaceuticals | Registered | 2023 |