| OAP3 | Octopus Apollo Vct PLC | 46.50 | 46.50 | 46.50 | 0 | 0.00 | | 0.00 | |
| OAUE | UBS Etf | 42.76 | 42.76 | 42.76 | 1.1K | 0.00 | | 0.00 | |
| OBD | Oxford Biodynamics PLC | 0.5500 | 0.4790 | 0.5000 | 25.73M | -0.0500 | | 9.09 | |
| OBI | Ondine Biomedical Inc. | 13.50 | 13.00 | 13.00 | 434.4K | 0.00 | | 0.00 | |
| OCDO | Ocado Group PLC | 241.9 | 231.8 | 238.4 | 1.73M | 4.0 | | 1.71 | |
| OCI | Oakley Capital Investments Limited | 570.0 | 556.0 | 558.0 | 126.4K | -4.0 | | 0.71 | |
| OCN | Ocean Wilsons (Holdings) LD | 1,150 | 1,130 | 1,135 | 44.1K | 0 | | 0.00 | |
| OE08 | Bank Of Montreal | 100.4 | 100.4 | 100.4 | 1M | 0.0 | | 0.00 | |
| OE61 | The Kingdom Of Morocco | 110.4 | 110.4 | 110.4 | 450K | 0.0 | | 0.00 | |
| OFG | Octopus Future Generations Vct PLC | 79.50 | 79.50 | 79.50 | 0 | 0.00 | | 0.00 | |
| OGDC | Oil And Gas Development Company Limited | 8.000 | 8.000 | 8.000 | 0 | 0.000 | | 0.00 | |
| OGG9 | Gold Bullion Securities LD | 330.8 | 330.8 | 330.8 | 100 | 47.1 | | 16.61 | |
| OGLD | Deutsche Boerse Commodities Gmbh | 116.5 | 115.4 | 115.7 | 3.9K | 1.0 | | 0.85 | |
| OGN | Origin Enterprises PLC | 3.860 | 3.850 | 3.850 | 126.8K | 0.000 | | 0.00 | |
| OGOL | Global X Metal Securities | 58.00 | 58.00 | 58.00 | 1.8K | -1.06 | | 1.79 | |
| OGZU | Wisdomtree Metal Securities Limited | 346.7 | 344.3 | 346.1 | 100 | 4.3 | | 1.27 | |
| OHGR | One Health Group PLC | 230.0 | 223.9 | 228.0 | 4.9K | 0.0 | | 0.00 | |
| OI20 | Kingdom Of Saudi Arabia (The) | 106.1 | 106.1 | 106.1 | 737K | 0.0 | | 0.00 | |
| OIG | Oryx International Growth Fund LTD | 1,320 | 1,283 | 1,320 | 6.8K | 23 | | 1.73 | |
| OIGB | Vaneck Ucits Etfs PLC | 15.15 | 14.77 | 14.83 | 2.4K | 0.10 | | 0.65 | |
| OIH | Orascom Investment Holding S.A.E | 0.0150 | 0.0140 | 0.0140 | 1.8K | 0.0000 | | 0.00 | |
| OIHV | Vaneck Ucits Etfs PLC | 20.08 | 19.79 | 19.88 | 2.6K | 0.30 | | 1.54 | |
| OIL2 | Wisdomtree Commodity Securities Limited | 650.5 | 635.8 | 637.3 | 834 | 2.6 | | 0.41 | |
| OIL3 | UBS AG | 81.27 | 81.27 | 81.27 | 0 | 0.26 | | 0.32 | |
| OILG | UBS AG | 7,448 | 7,448 | 7,448 | 0 | 20 | | 0.27 | |
| OILU | UBS AG | 121.9 | 121.9 | 121.9 | 0 | 0.3 | | 0.21 | |
| OIP9 | Shell International Finance B.V | 97.87 | 97.87 | 97.87 | 300K | 0.00 | | 0.00 | |
| OIT | Odyssean Investment Trust PLC | 162.8 | 158.8 | 162.5 | 163.2K | 2.5 | | 1.56 | |
| OM9S | Yorkshire Water Finance PLC | 69.60 | 69.60 | 69.60 | 100K | 0.00 | | 0.00 | |
| OMG | Oxford Metrics PLC | 46.00 | 43.00 | 45.20 | 2.1M | 6.20 | | 15.90 | |
| OMI | Orosur Mining INC | 28.00 | 26.00 | 27.50 | 4.71M | 0.75 | | 2.80 | |
| OMIP | One Media Ip Group PLC | 4.164 | 3.850 | 3.850 | 12K | 0.000 | | 0.00 | |
| OMU | Old Mutual Limited | 59.40 | 58.00 | 58.00 | 84.8K | -0.60 | | 1.02 | |
| OMXS | Ishares Iv PLC | 731.9 | 723.0 | 728.0 | 3.7K | 5.4 | | 0.74 | |
| ONDO | Ondo Insurtech PLC | 32.00 | 31.00 | 31.50 | 283.8K | -0.10 | | 0.32 | |
| ONT | Oxford Nanopore Technologies PLC | 144.1 | 138.6 | 138.6 | 1.04M | -3.3 | | 2.33 | |
| ONWD | Onward Opportunities Limited | 137.6 | 136.0 | 136.0 | 10.6K | 0.5 | | 0.37 | |
| OOA | Octopus Aim Vct PLC | 46.20 | 46.20 | 46.20 | 0 | 0.00 | | 0.00 | |
| OPEN | Ishares Iv PLC | 9.756 | 9.686 | 9.686 | 100 | 0.130 | | 1.36 | |
| OPG | Opg Power Ventures PLC | 5.900 | 5.711 | 5.800 | 301.6K | 0.000 | | 0.00 | |
| OPT | Optima Health PLC | 230.0 | 225.8 | 228.0 | 33.5K | 1.0 | | 0.44 | |
| OPTI | Optibiotix Health PLC | 9.500 | 8.500 | 8.900 | 342.7K | -0.350 | | 3.78 | |
| OQ12 | Standard Chartered PLC | 92.69 | 92.69 | 92.69 | 1.63M | 0.00 | | 0.00 | |
| ORC1 | Orchard Bond Finance PLC | 99.3 | 99.3 | 102.0 | 6.6K | 0.0 | | 0.00 | |
| ORCA | Orcadian Energy PLC | 9.250 | 9.250 | 9.250 | 100 | 0.000 | | 0.00 | |
| ORCH | Orchard Funding Group PLC | 59.70 | 58.00 | 59.50 | 3.7K | 0.00 | | 0.00 | |
| ORCP | Oracle Power PLC | 0.0500 | 0.0320 | 0.0430 | 0 | 0.0050 | | 13.16 | |
| ORIT | Octopus Renewables Infrastructure Trust | 62.20 | 61.20 | 61.70 | 2.14M | 0.00 | | 0.00 | |
| ORNT | Orient Telecoms PLC | 4.000 | 4.000 | 4.000 | 0 | 0.000 | | 0.00 | |
| ORR | Oriole Resources PLC | 0.3480 | 0.2600 | 0.3350 | 61.9M | 0.0500 | | 17.54 | |
| OS73 | Toyota Finance Australia Limited | 95.00 | 95.00 | 95.00 | 1M | 0.00 | | 0.00 | |
| OSB | Osb Group PLC | 565.0 | 553.5 | 555.5 | 479.3K | -7.0 | | 1.24 | |
| OSEC | Octopus Aim Vct 2 PLC | 36.40 | 36.40 | 36.40 | 0 | 0.00 | | 0.00 | |
| OSX5 | Source Markets Public Limited Company | 54.74 | 54.74 | 54.74 | 0 | 0.00 | | 0.00 | |
| OT06 | Derwent London PLC | 72.10 | 72.10 | 72.10 | 9.6K | 0.00 | | 0.00 | |
| OT1 | Oxford Technology 2 Venture Capital | 14.50 | 14.50 | 14.50 | 0 | 0.00 | | 0.00 | |
| OT3 | Oxford Technology 2 Venture Capital | 7.000 | 7.000 | 7.000 | 0 | 0.000 | | 0.00 | |
| OT4 | Oxford Technology 2 Venture Capital | 6.500 | 6.500 | 6.500 | 0 | 0.000 | | 0.00 | |
| OTB | On The Beach Group PLC | 228.5 | 222.5 | 224.5 | 485.2K | -0.5 | | 0.22 | |
| OTES | Hellenic Telecommunications Organization | 9.440 | 9.440 | 9.440 | 8 | 0.000 | | 0.00 | |
| OTPD | Otp Bank PLC | 17.00 | 17.00 | 17.00 | 0 | 0.00 | | 0.00 | |
| OTV2 | Octopus Titan Vct PLC | 26.00 | 24.50 | 24.50 | 3.1K | 0.00 | | 0.00 | |
| OUFU | Ossiam Irl Icav | 204.8 | 204.8 | 204.8 | 0 | 2.0 | | 0.96 | |
| OVB | Ovoca Bio PLC | 1.295 | 1.045 | 1.150 | 173.3K | 0.000 | | 0.00 | |
| OVCT | Oberon Aim Vct PLC | 23.10 | 23.10 | 23.10 | 433.6K | 0.00 | | 0.00 | |
| OVZA | Wisdomtree Metal Securities Limited | 131.5 | 129.5 | 131.2 | 100 | 2.2 | | 1.69 | |
| OVZB | Wisdomtree Metal Securities Limited | 123.9 | 120.6 | 121.7 | 131 | 3.4 | | 2.91 | |
| OVZC | Wisdomtree Metal Securities Limited | 41.73 | 41.06 | 41.50 | 1.3K | 0.86 | | 2.12 | |
| OXA1 | Db Etc PLC | 243.3 | 241.4 | 242.4 | 494 | 3.4 | | 1.42 | |
| OXA2 | Db Etc PLC | 282.5 | 277.3 | 280.0 | 377 | 7.2 | | 2.65 | |
| OXA5 | Db Etc PLC | 347.8 | 345.2 | 345.3 | 275 | 2.9 | | 0.85 | |
| OXA6 | Db Etc PLC | 426.9 | 419.1 | 420.0 | 100 | 13.5 | | 3.33 | |
| OXB | Oxford Biomedica PLC | 626.0 | 603.0 | 613.0 | 159.6K | -2.0 | | 0.33 | |
| OXH | Oxford Technology 2 Venture Capital | 6.000 | 6.000 | 6.000 | 0 | 0.000 | | 0.00 | |
| OXIG | Oxford Instruments PLC | 1,818 | 1,750 | 1,818 | 139.8K | 36 | | 2.02 | |
| OZ76 | Nationwide Building Society | 98.25 | 98.25 | 98.25 | 578K | 0.00 | | 0.00 | |