| OAP3 | Octopus Apollo VCT PLC | 46.30 | 46.30 | 46.30 | 0 | 0.00 | | 0.00 | |
| OAUE | UBS Etf | 42.76 | 42.76 | 42.76 | 1.7K | 0.00 | | 0.00 | |
| OBD | Oxford Biodynamics PLC | 0.3100 | 0.2610 | 0.2940 | 20.67M | -0.0060 | | 2.00 | |
| OBI | Ondine Biomedical Inc | 9.500 | 8.500 | 8.500 | 542.2K | -0.500 | | 5.56 | |
| OCDO | Ocado Group PLC | 231.4 | 223.5 | 231.3 | 163.34M | 1.4 | | 0.61 | |
| OCI | Oakley Capital Investments Limited | 513.0 | 504.0 | 508.0 | 792.5K | 0.0 | | 0.00 | |
| OCN | Ocean Wilsons (Holdings) LD | 1,200 | 1,175 | 1,180 | 33.8K | 0 | | 0.00 | |
| OCTF | First Trust Global Funds Public Limited | 2,013 | 2,013 | 2,025 | 150 | -1 | | 0.02 | |
| OE08 | Bank Of Montreal | 100.4 | 100.4 | 100.4 | 1.0M | 0.0 | | 0.00 | |
| OE61 | The Kingdom Of Morocco | 108.0 | 108.0 | 108.0 | 200.0K | 0.0 | | 0.00 | |
| OFG | Octopus Future Generations VCT plc | 79.50 | 79.50 | 79.50 | 0 | 0.00 | | 0.00 | |
| OGDC | OGDC | 8.000 | 8.000 | 8.000 | 0 | 0.000 | | 0.00 | |
| OGG9 | Gold Bullion Securities LD | 382.7 | 380.7 | 382.7 | 0 | 6.0 | | 1.59 | |
| OGLD | Deutsche Boerse Commodities Gmbh | 135.0 | 131.7 | 134.4 | 5.6K | 2.0 | | 1.53 | |
| OGN | Origin Enterprises Plc | 4.330 | 4.305 | 4.305 | 2.5K | 0.055 | | 1.29 | |
| OGOL | Global X Metal Securities | 56.35 | 56.35 | 56.35 | 297 | -7.86 | | 12.24 | |
| OGZU | Wisdomtree Metal Securities Limited | 399.6 | 392.5 | 399.6 | 100 | 9.4 | | 2.42 | |
| OHGR | One Health Group Plc | 224.0 | 223.3 | 223.3 | 15.0K | -0.7 | | 0.32 | |
| OI20 | Kingdom Of Saudi Arabia (The) | 105.3 | 105.3 | 105.3 | 11.0M | 0.0 | | 0.00 | |
| OIG | Oryx International Growth Fund | 1,365 | 1,310 | 1,352 | 22.6K | -4 | | 0.26 | |
| OIGB | Vaneck Ucits Etfs Plc - Vaneck Oil | 21.59 | 20.92 | 21.55 | 55.1K | 0.72 | | 3.46 | |
| OIH | Orascom Investment Holding S.A.E | 0.0150 | 0.0140 | 0.0140 | 1.8K | 0.0000 | | 0.00 | |
| OIHV | VanEck Oil Services ETF A USD Acc | 29.40 | 28.43 | 29.39 | 45.8K | 1.19 | | 4.20 | |
| OIL2 | Wisdomtree Commodity Securities Limited | 763.5 | 724.0 | 759.8 | 39.0K | 18.6 | | 2.51 | |
| OIL3 | UBS AG | 90.40 | 90.40 | 90.40 | 432 | 1.09 | | 1.22 | |
| OILG | UBS AG UBS ETC (CMCI WTI) GBP | 8,043 | 7,872 | 8,043 | 0 | 116 | | 1.46 | |
| OILU | UBS AG | 129.9 | 129.6 | 131.9 | 7 | -0.3 | | 0.19 | |
| OIP9 | Shell International Finance B.V | 97.70 | 97.70 | 97.70 | 0 | 0.00 | | 0.00 | |
| OIT | Odyssean Investment Trust PLC | 184.0 | 180.5 | 182.9 | 449.2K | -1.1 | | 0.58 | |
| OM9S | Yorkshire Water Finance PLC | 69.60 | 69.60 | 69.60 | 100.0K | 0.00 | | 0.00 | |
| OMG | Oxford Metrics plc | 59.60 | 58.20 | 58.94 | 925.9K | -0.46 | | 0.78 | |
| OMI | Orosur Mining Inc | 34.00 | 32.85 | 34.00 | 3.13M | 2.00 | | 6.25 | |
| OMIP | One Media iP Group Plc | 4.000 | 3.200 | 4.000 | 438 | 0.400 | | 11.11 | |
| OMU | Old Mutual Ltd | 72.52 | 71.16 | 71.80 | 133.2K | 0.00 | | 0.00 | |
| OMXS | iShares OMX Stockholm Capped UCITS | 839.8 | 824.8 | 839.8 | 20.3K | 8.8 | | 1.05 | |
| ONDO | Ondo InsurTech PLC | 17.50 | 17.00 | 17.03 | 736.5K | -0.23 | | 1.30 | |
| ONT | Oxford Nanopore Technologies Ltd | 148.9 | 140.4 | 142.7 | 77.2M | -3.5 | | 2.42 | |
| ONWD | Onward Opportunities Ltd | 146.0 | 145.0 | 145.0 | 15.5K | -0.5 | | 0.33 | |
| OOA | Octopus Aim Vct Plc | 45.40 | 44.00 | 45.40 | 1.0K | 0.00 | | 0.00 | |
| OPEN | iShares Thomson Reuters Inclusion and | 10.22 | 10.20 | 10.22 | 100 | -0.04 | | 0.43 | |
| OPG | Opg Power Ventures PLC | 5.700 | 5.300 | 5.400 | 1.25M | 0.000 | | 0.00 | |
| OPT | Optima Health plc | 215.0 | 212.0 | 213.5 | 420.7K | 0.0 | | 0.00 | |
| OPTI | OptiBiotix Health Plc | 8.000 | 7.300 | 7.620 | 124.8K | -0.030 | | 0.39 | |
| OQ12 | Standard Chartered PLC | 92.40 | 92.40 | 92.54 | 0 | 0.00 | | 0.00 | |
| ORC1 | Orchard Bond Finance PLC | 100.7 | 100.7 | 101.4 | 0 | 0.0 | | 0.00 | |
| ORCA | Orcadian Energy PLC | 18.00 | 16.50 | 18.00 | 54.8K | 0.75 | | 4.35 | |
| ORCH | Orchard Funding Group PLC | 65.00 | 60.33 | 61.50 | 946.9K | 1.50 | | 2.50 | |
| ORCP | Oracle Coalfields Plc | 0.0600 | 0.0450 | 0.0550 | 134.5M | 0.0020 | | 3.77 | |
| ORIT | Octopus Renewables Infrastructure Trust | 57.20 | 55.50 | 57.19 | 1.09M | 1.09 | | 1.94 | |
| ORNT | Orient Telecoms | 4.000 | 3.000 | 4.000 | 0 | 0.000 | | 0.00 | |
| ORR | Oriole Resources PLC | 0.3600 | 0.3300 | 0.3500 | 26.5M | 0.0100 | | 2.94 | |
| OS73 | Toyota Finance Australia Limited | 95.93 | 95.93 | 95.93 | 0 | 0.00 | | 0.00 | |
| OSB | OneSavings Bank PLC | 615.5 | 598.0 | 603.0 | 56.66M | 0.5 | | 0.08 | |
| OSEC | Octopus Aim VCT 2 PLC | 36.00 | 35.00 | 36.00 | 1.0K | 0.00 | | 0.00 | |
| OSX5 | Source Markets Public Limited Company | 57.43 | 57.34 | 57.34 | 0 | -0.84 | | 1.44 | |
| OT06 | Derwent London PLC | 72.10 | 72.10 | 72.10 | 9.6K | 0.00 | | 0.00 | |
| OT1 | Oxford Technology 2 Venture Capital | 17.00 | 14.50 | 14.50 | 0 | 0.00 | | 0.00 | |
| OT3 | Oxford Technology 2 Venture Capital | 8.500 | 7.500 | 7.500 | 0 | 0.000 | | 0.00 | |
| OT4 | Oxford Technology 2 Venture Capital | 8.500 | 7.500 | 7.500 | 0 | 0.000 | | 0.00 | |
| OTB | On The Beach Group PLC | 210.9 | 203.0 | 210.0 | 13.65M | 2.5 | | 1.20 | |
| OTES | Hellenic Telecommunications Organization | 9.700 | 9.700 | 9.700 | 0 | 0.000 | | 0.00 | |
| OTPD | OTP Bank Plc | 17.00 | 17.00 | 17.00 | 0 | 0.00 | | 0.00 | |
| OTV2 | Octopus Titan VCT | 21.50 | 20.40 | 21.50 | 1.7K | 0.00 | | 0.00 | |
| OUFU | Ossiam Irl Icav | 207.1 | 207.1 | 205.2 | 3 | -1.0 | | 0.49 | |
| OVB | Ovoca Bio PLC | 7.920 | 7.000 | 7.300 | 378.9K | 0.050 | | 0.69 | |
| OVCT | Oberon Aim Vct PLC | 25.70 | 25.70 | 25.70 | 0 | 0.00 | | 0.00 | |
| OVZA | Wisdomtree Metal Securities Limited | 162.0 | 152.4 | 161.0 | 100 | 1.8 | | 1.14 | |
| OVZB | Wisdomtree Metal Securities Limited | 132.2 | 126.1 | 132.0 | 100 | 1.5 | | 1.11 | |
| OVZC | Wisdomtree Metal Securities Limited | 59.41 | 55.62 | 58.06 | 18.0K | -0.79 | | 1.35 | |
| OXA1 | Db Etc PLC | 281.5 | 276.3 | 281.5 | 317 | 5.3 | | 1.93 | |
| OXA2 | Db Etc PLC | 401.1 | 381.1 | 400.7 | 178 | 0.8 | | 0.19 | |
| OXA5 | Db Etc PLC | 400.5 | 393.2 | 400.5 | 100 | 5.5 | | 1.39 | |
| OXA6 | Db Etc PLC | 609.4 | 578.0 | 604.1 | 395 | -93.4 | | 13.39 | |
| OXB | Oxford BioMedica PLC | 815.0 | 790.0 | 807.0 | 3.48M | -5.0 | | 0.62 | |
| OXH | Oxford Technology 2 Venture Capital | 7.000 | 7.000 | 7.000 | 0 | 0.000 | | 0.00 | |
| OXIG | Oxford Instruments PLC | 2,460 | 2,365 | 2,450 | 8.45M | 40 | | 1.66 | |
| OZ76 | Nationwide Building Society | 98.25 | 98.25 | 98.25 | 578.0K | 0.00 | | 0.00 | |