| OLEN 2163120 · TMA1213285 | OLEN Group of Companies Ltd. | 36 Finance | Registered | 2023 |
| OLIN 1756734 · TMA1068643 · design | OLIN CORPORATION | 1 Chemicals17 Rubber | Registered | 2020 |
| OLIN 1756730 · TMA1068642 | OLIN CORPORATION | 1 Chemicals17 Rubber | Registered | 2020 |
| OLON 1671366 · TMA957406 | Olon Industries (2008), Inc. | 6 Metal17 Rubber19 Building+1 | Registered | 2016 |
| OLIN 0361924 · TMA195641 · design | OLIN CORPORATION | 6 Metal | Registered | 1973 |
| OLIN 0222662 · UCA48499 | OLIN CORPORATION | 13 Firearms | Registered | 1953 |
| OLIN 2280269 · design | Tea Horse Road Trading Company Inc. | 21 Housewares | Pending | 2023 |
| OLM 1016910 · TMA541151 | an individual | 9 Electronics36 Finance41 Education+1 | Registered | 2001 |
| Ollny 2075395 · TMA1282289 | Shenzhenshi Meimao Technology Co. Ltd. | 11 Lighting | Registered | 2025 |
| OLANA 1972686 · TMA1255710 | Home Delivery Incontinent Supplies Co. (HDIS) | 5 Pharmaceuticals10 Medical | Registered | 2024 |
| OLLIN 1805629 · TMA1001259 | Colebrook Bosson & Saunders (Products) Limited | 9 Electronics | Registered | 2018 |
| OILON 1473499 · TMA811215 | an individual | 9 Electronics11 Lighting | Registered | 2011 |
| OLÈNE 1268548 · TMA760436 | an individual | 3 Cosmetics | Registered | 2010 |
| OLLIN 2353516 | Ollin Biosciences Inc. | 5 Pharmaceuticals | Pending | 2024 |
| OLLEN 2329559 | an individual | 12 Vehicles | Pending | 2024 |
| Oliem 2238140 · TMA1205510 | 9426-2193 Québec inc. | 9 Electronics12 Vehicles35 Advertising | Registered | 2023 |
| OLOAM 2234695 · TMA1254171 | Sewtech Inc. | 20 Furniture24 Textiles | Registered | 2024 |
| OLIYuMi 2131280 · TMA1209743 | an individual | 16 Paper28 Toys | Registered | 2023 |
| OLYMMA 2117843 · TMA1184174 | Owner not shown | 9 Electronics25 Clothing | Registered | 2023 |
| OLOWEN 2043562 · TMA1149047 · design | Green Nature Health Care Products Inc. | 5 Pharmaceuticals10 Medical21 Housewares | Registered | 2022 |
| OLMI 1971239 · TMA1281750 · design | an individual | 7 Machines | Registered | 2025 |
| OLAIAN 1840699 · TMA1070472 | PROJETCLUB, SA | 9 Electronics18 Leather25 Clothing+1 | Registered | 2020 |
| OLAM 1781163 · TMA1054892 · design | Olam Global Agri Pte. Ltd. | 1 Chemicals17 Rubber19 Building+10 | Registered | 2019 |
| OLAM 1781161 · TMA1002046 | Olam Global Agri Pte. Ltd. | 1 Chemicals17 Rubber19 Building+10 | Registered | 2018 |
| OLMA 1770563 · TMA980823 · design | an individual | 35 Advertising41 Education42 Science+1 | Registered | 2017 |