| 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 | 11 | 0.00 | | 0.00 | |
| OBD | Oxford Biodynamics PLC | 0.2400 | 0.2290 | 0.2350 | 14.86M | 0.0050 | | 2.17 | |
| OBI | Ondine Biomedical Inc. | 10.000 | 9.000 | 9.000 | 343.2K | -0.750 | | 7.69 | |
| OCDO | Ocado Group PLC | 247.4 | 236.9 | 244.4 | 1.89M | -4.1 | | 1.65 | |
| OCI | Oakley Capital Investments Limited | 570.0 | 558.0 | 564.0 | 149.9K | 4.0 | | 0.71 | |
| OCN | Ocean Wilsons (Holdings) LD | 1,200 | 1,175 | 1,180 | 33.8K | 0 | | 0.00 | |
| OCTF | First Trust Global Funds Public Limited | 2,038 | 2,038 | 2,038 | 0 | -2 | | 0.11 | |
| OE08 | Bank Of Montreal | 100.4 | 100.4 | 100.4 | 1.0M | 0.0 | | 0.00 | |
| OE61 | The Kingdom Of Morocco | 108.4 | 108.4 | 108.4 | 1.47M | 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 | 330.4 | 330.4 | 330.4 | 3.1K | 0.0 | | 0.00 | |
| OGLD | Deutsche Boerse Commodities Gmbh | 121.3 | 120.7 | 121.3 | 671 | 2.1 | | 1.72 | |
| OGN | Origin Enterprises PLC | 4.150 | 4.150 | 4.150 | 0 | 0.141 | | 3.52 | |
| OGOL | Global X Metal Securities | 56.35 | 56.35 | 56.35 | 128 | 0.00 | | 0.00 | |
| OGZU | Wisdomtree Metal Securities Limited | 360.1 | 359.4 | 359.6 | 0 | 4.5 | | 1.27 | |
| OHGR | One Health Group PLC | 256.8 | 251.0 | 254.0 | 9.0K | 1.8 | | 0.71 | |
| OI20 | Kingdom Of Saudi Arabia (The) | 106.2 | 106.2 | 106.2 | 2.68M | 0.0 | | 0.00 | |
| OIG | Oryx International Growth Fund LTD | 1,290 | 1,210 | 1,290 | 3.0K | 60 | | 4.88 | |
| OIGB | Vaneck Ucits Etfs PLC | 17.28 | 16.95 | 17.22 | 4.9K | 0.26 | | 1.51 | |
| OIH | Orascom Investment Holding S.A.E | 0.0150 | 0.0140 | 0.0140 | 1.8K | 0.0000 | | 0.00 | |
| OIHV | Vaneck Ucits Etfs PLC | 23.23 | 22.77 | 23.17 | 4.4K | 0.38 | | 1.65 | |
| OIL2 | Wisdomtree Commodity Securities Limited | 629.0 | 628.8 | 628.8 | 100 | 22.8 | | 3.75 | |
| OIL3 | UBS AG | 81.55 | 81.55 | 81.55 | 0 | 1.74 | | 2.18 | |
| OILG | UBS AG | 7,404 | 7,404 | 7,404 | 0 | 125 | | 1.72 | |
| OILU | UBS AG | 121.2 | 121.2 | 121.2 | 0 | 2.1 | | 1.74 | |
| OIP9 | Shell International Finance B.V | 97.70 | 97.70 | 97.70 | 0 | 0.00 | | 0.00 | |
| OIT | Odyssean Investment Trust PLC | 172.0 | 166.6 | 167.0 | 77.9K | 0.3 | | 0.18 | |
| OM9S | Yorkshire Water Finance PLC | 69.60 | 69.60 | 69.60 | 100.0K | 0.00 | | 0.00 | |
| OMG | Oxford Metrics PLC | 47.50 | 45.10 | 47.40 | 128.2K | 0.60 | | 1.28 | |
| OMI | Orosur Mining INC | 23.50 | 21.60 | 22.85 | 1.44M | 1.25 | | 5.79 | |
| OMIP | One Media Ip Group PLC | 3.750 | 3.750 | 3.750 | 0 | 0.000 | | 0.00 | |
| OMU | Old Mutual Limited | 65.60 | 63.40 | 64.40 | 115.9K | -0.40 | | 0.62 | |
| OMXS | Ishares Iv PLC | 769.3 | 763.3 | 765.9 | 3.8K | -2.4 | | 0.31 | |
| ONDO | Ondo Insurtech PLC | 22.00 | 21.80 | 21.85 | 211.4K | 0.00 | | 0.00 | |
| ONT | Oxford Nanopore Technologies PLC | 129.4 | 123.2 | 129.4 | 1.4M | 3.2 | | 2.54 | |
| ONWD | Onward Opportunities Limited | 143.0 | 142.5 | 142.5 | 3.0K | -0.5 | | 0.33 | |
| OOA | Octopus Aim Vct PLC | 46.60 | 46.60 | 46.60 | 0 | 0.00 | | 0.00 | |
| OPEN | Ishares Iv PLC | 10.05 | 9.99 | 10.03 | 1.6K | 0.00 | | 0.04 | |
| OPG | Opg Power Ventures PLC | 5.800 | 5.000 | 5.440 | 1.77M | -0.060 | | 1.09 | |
| OPT | Optima Health PLC | 200.0 | 192.0 | 196.5 | 49.1K | 4.5 | | 2.34 | |
| OPTI | Optibiotix Health PLC | 6.750 | 6.650 | 6.750 | 112.1K | -0.250 | | 3.57 | |
| OQ12 | Standard Chartered PLC | 92.46 | 92.46 | 92.46 | 0 | 0.00 | | 0.00 | |
| ORC1 | Orchard Bond Finance PLC | 100.0 | 100.0 | 101.0 | 0 | 0.0 | | 0.00 | |
| ORCA | Orcadian Energy PLC | 13.60 | 12.73 | 13.25 | 20.5K | 0.75 | | 6.00 | |
| ORCH | Orchard Funding Group PLC | 62.00 | 58.00 | 60.50 | 23.1K | -1.50 | | 2.42 | |
| ORCP | Oracle Power PLC | 0.0450 | 0.0350 | 0.0380 | 41.84M | 0.0010 | | 2.70 | |
| ORIT | Octopus Renewables Infrastructure Trust | 60.10 | 57.40 | 58.30 | 876.1K | -0.20 | | 0.34 | |
| ORNT | Orient Telecoms PLC | 4.000 | 4.000 | 4.000 | 0 | 0.000 | | 0.00 | |
| ORR | Oriole Resources PLC | 0.2980 | 0.2600 | 0.2750 | 21.53M | -0.0120 | | 4.18 | |
| OS73 | Toyota Finance Australia Limited | 95.00 | 95.00 | 95.00 | 1.0M | 0.00 | | 0.00 | |
| OSB | Osb Group PLC | 634.5 | 626.5 | 633.5 | 472.3K | 1.5 | | 0.24 | |
| OSEC | Octopus Aim Vct 2 PLC | 35.20 | 35.20 | 35.20 | 0 | 0.00 | | 0.00 | |
| OSX5 | Source Markets Public Limited Company | 55.49 | 55.25 | 55.37 | 2 | 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 | 231.5 | 226.5 | 230.5 | 175.0K | 1.5 | | 0.66 | |
| 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 | 24.50 | 23.00 | 24.50 | 32.1K | 1.50 | | 6.52 | |
| OUFU | Ossiam Irl Icav | 207.1 | 207.1 | 205.2 | 3 | -1.0 | | 0.49 | |
| OVB | Ovoca Bio PLC | 1.295 | 1.045 | 1.150 | 173.3K | 0.000 | | 0.00 | |
| OVCT | Oberon Aim Vct PLC | 25.30 | 25.30 | 25.30 | 0 | 0.00 | | 0.00 | |
| OVZA | Wisdomtree Metal Securities Limited | 162.6 | 159.8 | 160.9 | 100 | 6.8 | | 4.39 | |
| OVZB | Wisdomtree Metal Securities Limited | 139.8 | 135.1 | 135.6 | 12.7K | 2.7 | | 2.03 | |
| OVZC | Wisdomtree Metal Securities Limited | 53.81 | 53.14 | 53.21 | 5.7K | 1.12 | | 2.16 | |
| OXA1 | Db Etc PLC | 254.3 | 253.1 | 254.3 | 0 | 4.8 | | 1.93 | |
| OXA2 | Db Etc PLC | 365.0 | 361.3 | 361.3 | 935 | 8.0 | | 2.25 | |
| OXA5 | Db Etc PLC | 362.2 | 360.4 | 362.2 | 100 | 7.3 | | 2.05 | |
| OXA6 | Db Etc PLC | 552.4 | 529.0 | 529.0 | 100 | -5.9 | | 1.10 | |
| OXB | Oxford Biomedica PLC | 586.0 | 566.3 | 585.0 | 177.2K | 9.0 | | 1.56 | |
| OXH | Oxford Technology 2 Venture Capital | 6.000 | 6.000 | 6.000 | 0 | 0.000 | | 0.00 | |
| OXIG | Oxford Instruments PLC | 2,100 | 2,065 | 2,080 | 414.1K | -15 | | 0.72 | |
| OZ76 | Nationwide Building Society | 98.25 | 98.25 | 98.25 | 578.0K | 0.00 | | 0.00 | |