| Scottish Power | Iberdrola | utilities and power generation | energy market violation | 2023 | UK-OFGEM | £440,000 |
| British Gas | Centrica | utilities and power generation | energy market violation | 2023 | UK-OFGEM | £3,370,000 |
| E.ON | E.ON | utilities and power generation | energy market violation | 2023 | UK-OFGEM | £1,720,000 |
| Scottish Power | Iberdrola | utilities and power generation | energy market violation | 2023 | UK-OFGEM | £1,240,000 |
| SSE | SSE PLC | utilities and power generation | energy market violation | 2023 | UK-OFGEM | £252,000 |
| Severn Trent PLC | Severn Trent PLC | utilities and power generation | price-fixing or anti-competitive practices | 2012 | UK-OFWAT | £0 |
| Thames Water | Thames Water Utilities Ltd. | utilities and power generation | price-fixing or anti-competitive practices | 2022 | UK-OFWAT | £0 |
| Bristol Water | Pennon Group PLC | utilities and power generation | price-fixing or anti-competitive practices | 2015 | UK-OFWAT | £0 |
| Dorenell Windfarm Limited | EDF-Electricite de France | utilities and power generation | energy market violation | 2024 | UK-OFGEM | £5,530,000 |
| British Gas Trading Limited | Centrica | utilities and power generation | price-fixing or anti-competitive practices | 2016 | UK-CMA | £0 |
| E.ON Energy Solutions Limited | E.ON | utilities and power generation | price-fixing or anti-competitive practices | 2016 | UK-CMA | £0 |
| EDF Energy Customers plc | EDF-Electricite de France | utilities and power generation | price-fixing or anti-competitive practices | 2016 | UK-CMA | £0 |
| Npower Group plc | E.ON | utilities and power generation | price-fixing or anti-competitive practices | 2016 | UK-CMA | £0 |
| Scottish Power Energy Retail Limited | Iberdrola | utilities and power generation | price-fixing or anti-competitive practices | 2016 | UK-CMA | £0 |
| Southern Electric Gas Limited | OVO Energy | utilities and power generation | price-fixing or anti-competitive practices | 2016 | UK-CMA | £0 |
| Avanti Gas Limited | UGI Corp. | utilities and power generation | price-fixing or anti-competitive practices | 2012 | UK-OFT | £0 |
| National Grid Electricity System Operator Limited | National Grid | utilities and power generation | energy market violation | 2021 | UK-OFGEM | £1,500,000 |
| E.ON | E.ON | utilities and power generation | consumer protection violation | 2021 | UK-OFGEM | £682,351 |
| SSE Energy Services | OVO Energy | utilities and power generation | energy market violation | 2021 | UK-OFGEM | £20,000 |
| British Gas/ Centrica | Centrica | utilities and power generation | consumer protection violation | 2021 | UK-OFGEM | £1,660,272 |
| British Gas | Centrica | utilities and power generation | consumer protection violation | 2020 | UK-OFGEM | £1,728,070 |
| EDF Energy | EDF-Electricite de France | utilities and power generation | consumer protection violation | 2020 | UK-OFGEM | £3,237 |
| RWE Generation UK plc | RWE AG | utilities and power generation | energy market violation | 2020 | UK-OFGEM | £4,500,000 |
| Engie Global Markets | Engie | utilities and power generation | energy market manipulation | 2019 | UK-OFGEM | £2,128,236 |
| SSE Energy Services | OVO Energy | utilities and power generation | consumer protection violation | 2019 | UK-OFGEM | £4,775,705 |
| npower Direct Ltd. and npower Ltd. and npower Northern Ltd. and npower Yorkshire Ltd. | E.ON | utilities and power generation | energy market violation | 2018 | UK-OFGEM | £2,400,000 |
| British Gas Trading Limited | Centrica | utilities and power generation | energy market violation | 2017 | UK-OFGEM | £4,500,000 |
| SSE plc | SSE PLC | utilities and power generation | price-fixing or anti-competitive practices | 2016 | UK-OFGEM | £0 |
| E.ON UK Plc and E.ON Energy Solutions Ltd. | E.ON | utilities and power generation | energy market violation | 2015 | UK-OFGEM | £7,000,000 |
| Drax PowerLimited | Drax Group PLC | utilities and power generation | energy market violation | 2015 | UK-OFGEM | £25,000,000 |
| British Gas | Centrica | utilities and power generation | energy market violation | 2015 | UK-OFGEM | £10,600,000 |
| ScottishPower Energy Retail Limited and ScottishPower Generation Limited | Iberdrola | utilities and power generation | energy market violation | 2015 | UK-OFGEM | £2,400,000 |
| SSE plc | SSE PLC | utilities and power generation | energy market violation | 2015 | UK-OFGEM | £1,750,000 |
| British Gas | Centrica | utilities and power generation | energy market violation | 2015 | UK-OFGEM | £500,000 |
| GDF Suez/IPM | Engie | utilities and power generation | energy market violation | 2015 | UK-OFGEM | £450,000 |
| npower Direct Ltd. and npower Ltd. and npower Northern Ltd. and npower Yorkshire Ltd. | E.ON | utilities and power generation | energy market violation | 2014 | UK-OFGEM | £125,328 |
| Opus Energy Limited | Drax Group PLC | utilities and power generation | energy market violation | 2012 | UK-OFGEM | £125,000 |
| British Gas Trading Limited | Centrica | utilities and power generation | energy market violation | 2011 | UK-OFGEM | £1,000,000 |
| National Grid Gas plc | National Gas Transmission PLC | utilities and power generation | energy market violation | 2011 | UK-OFGEM | £8,000,000 |
| Scottish Hydro Electric Power Distribution plc | SSE PLC | utilities and power generation | energy market violation | 2011 | UK-OFGEM | £500,000 |
| Utility Warehouse | Telecom Plus PLC | utilities and power generation | consumer protection violation | 2021 | UK-OFGEM | £1,500,000 |
| National Grid Electricity Transmission plc and Scottish Power Transmission plc | National Grid | utilities and power generation | consumer protection violation | 2021 | UK-OFGEM | £158,000,000 |
| Drax Pumped Storage Limited | Drax Group PLC | utilities and power generation | energy market violation | 2023 | UK-OFGEM | £6,120,000 |
| EDF Energy (Thermal Generation) Limited | EDF-Electricite de France | utilities and power generation | energy market violation | 2020 | UK-OFGEM | £6,000,000 |
| SSE Generation Limited | SSE PLC | utilities and power generation | energy market violation | 2020 | UK-OFGEM | £2,060,000 |
| SSE Energy Services | OVO Energy | utilities and power generation | energy market violation | 2020 | UK-OFGEM | £1,200,000 |
| Cadent Gas Limited | Cadent Gas Limited | utilities and power generation | energy market violation | 2019 | UK-OFGEM | £44,000,000 |
| SSE Energy Services | OVO Energy | utilities and power generation | energy market violation | 2019 | UK-OFGEM | £700,000 |
| SSE Plc | SSE PLC | utilities and power generation | energy market violation | 2019 | UK-OFGEM | £705,000 |
| EDF Energy | EDF-Electricite de France | utilities and power generation | energy market violation | 2018 | UK-OFGEM | £350,000 |
| National Grid | National Grid | utilities and power generation | energy market violation | 2016 | UK-OFGEM | £3,000,000 |
| SSE | SSE PLC | utilities and power generation | energy market violation | 2015 | UK-OFGEM | £100,000 |
| SSE Generation Limited | SSE PLC | utilities and power generation | energy market violation | 2023 | UK-OFGEM | £9,780,000 |
| BT Group plc | BT | telecommunications | price-fixing or anti-competitive practices | 2020 | UK-OFCOM | £6,300,000 |
| British Telecommunications plc | BT | telecommunications | price-fixing or anti-competitive practices | 2017 | UK-OFCOM | £300,000 |
| British Telecommunications plc | BT | telecommunications | price-fixing or anti-competitive practices | 2017 | UK-OFCOM | £42,000,000 |
| British Telecommunications plc | BT | telecommunications | consumer protection violation | 2014 | UK-OFCOM | £1,200,000 |
| British Telecommunications plc | BT | telecommunications | price-fixing or anti-competitive practices | 2013 | UK-OFCOM | £2,896,800 |
| British Telecommunications plc | BT | telecommunications | price-fixing or anti-competitive practices | 2012 | UK-OFCOM | £117,042,000 |
| Motorola Solutions UK Limited | Motorola Solutions | telecommunications | price-fixing or anti-competitive practices | 2022 | UK-OFCOM | £0 |
| Motorola Solutions, Inc. | Motorola Solutions | telecommunications | price-fixing or anti-competitive practices | 2023 | UK-CMA | £0 |
| Marks and Spencer plc | Marks and Spencer Group PLC | retailing | price-fixing or anti-competitive practices | 2023 | UK-CMA | £0 |
| Co-operative Group Limited | Co-operative Group Limited | retailing | Groceries Supply Code of Conduct violation | 2019 | UK-GCA | £0 |
| Tesco | Tesco PLC | retailing | Groceries Supply Code of Conduct violation | 2016 | UK-GCA | £0 |
| Tesco plc | Tesco PLC | retailing | price-fixing or anti-competitive practices | 2020 | UK-CMA | £0 |
| Tesco Stores Limited and Tesco Holdings Limited and Tesco plc | Tesco PLC | retailing | price-fixing or anti-competitive practices | 2013 | UK-OFT | £6,500,000 |
| Sainsbury's Supermarkets Limited and J Sainsbury plc | J Sainsbury PLC | retailing | price-fixing or anti-competitive practices | 2011 | UK-OFT | £11,040,000 |
| Asda Stores Ltd. and Asda Group Ltd. and Wal-Mart Stores (UK) Ltd. and Broadstreet Great Wilson Europe Ltd. | EG Group | retailing | price-fixing or anti-competitive practices | 2011 | UK-OFT | £9,100,000 |
| JD Sports | JD Sports Fashion | retailing | price-fixing or anti-competitive practices | 2022 | UK-CMA | £4,320,000 |
| JD Sports Fashion Plc | JD Sports Fashion | retailing | price-fixing or anti-competitive practices | 2022 | UK-CMA | £1,485,000 |
| Waitrose | John Lewis Partnership | retailing | price-fixing or anti-competitive practices | 2022 | UK-CMA | £0 |
| J Sainsbury plc | J Sainsbury PLC | retailing | price-fixing or anti-competitive practices | 2023 | UK-CMA | £0 |
| Asda | EG Group | retailing | price-fixing or anti-competitive practices | 2023 | UK-CMA | £0 |
| JD Sports Fashion plc | JD Sports Fashion | retailing | price-fixing or anti-competitive practices | 2023 | UK-CMA | £0 |
| Asda Group Ltd | EG Group | retailing | price-fixing or anti-competitive practices | 2023 | UK-CMA | £30,000 |
| Wm Morrison Supermarkets Limited | Clayton Dubilier & Rice | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2023 | UK-CMA | £0 |
| Advanz Pharma | Nordic Capital | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2021 | UK-CMA | £40,900,000 |
| Safeway Stores Limited and Strores Group Limited and Safeway Limited | Clayton Dubilier & Rice | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2011 | UK-OFT | £5,690,000 |
| Focus Pharmaceuticals Limited and Focus Pharma Holdings Limited | Nordic Capital | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2022 | UK-CMA | £549,343 |
| Focus Pharmaceuticals Ltd. and Focus Pharma Holdings Ltd. and Mercury Pharma Group Ltd. | Nordic Capital | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2022 | UK-CMA | £921,357 |
| Focus Pharmaceuticals Limited and Mercury Pharma Group Ltd. and Cinven Partners LLP et al. | Nordic Capital | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2022 | UK-CMA | £1,843,380 |
| Cinven Capital Management (V) GP Ltd. and Cinven Partners LLP et al. | Cinven Group | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2022 | UK-CMA | £4,856,620 |
| Focus Pharmaceuticals Limited and Mercury Pharma Group Ltd. and Concordia Investments (Jersey) Ltd. and Advanz Pharma Corp. Ltd. et al. | Nordic Capital | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2022 | UK-CMA | £7,288,853 |
| Cinven | Cinven Group | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2021 | UK-CMA | £37,100,000 |
| HGCapital | Hg Capital | private equity (including portfolio companies) | price-fixing or anti-competitive practices | 2021 | UK-CMA | £6,200,000 |
| Auden Mckenzie (Pharma Division) Ltd. and Accord-UK Ltd. | Intas Pharmaceuticals Ltd. | pharmaceuticals | price-fixing or anti-competitive practices | 2020 | UK-CMA | £2,882,238 |
| GlaxoSmithKline plc and GlaxoSmithKline UK Ltd. and SmithKline Beecham Ltd. and Beecham Group plc | GlaxoSmithKline | pharmaceuticals | price-fixing or anti-competitive practices | 2016 | UK-CMA | £22,000,000 |
| Actavis UK Ltd. | Intas Pharmaceuticals Ltd. | pharmaceuticals | price-fixing or anti-competitive practices | 2016 | UK-CMA | £1,542,860 |
| DePuy International Limited | Johnson & Johnson | pharmaceuticals | bribery | 2011 | UK-SFO | £4,829,000 |
| Alliance Pharmaceuticals Limited and Alliance Pharma plc | Alliance Pharma PLC | pharmaceuticals | price-fixing or anti-competitive practices | 2022 | UK-CMA | £7,900,000 |
| Pfizer Limited | Pfizer | pharmaceuticals | price-fixing or anti-competitive practices | 2022 | UK-CMA | £63,300,000 |
| Auden Mckenzie and Actavis UK | Intas Pharmaceuticals Ltd. | pharmaceuticals | price-fixing or anti-competitive practices | 2023 | UK-CMA | £130,000,000 |
| John Wood Group PLC | Wood Group | oilfield services and supplies | bribery | 2017 | UK-COPFS | £6,460,000 |
| Amec Foster Wheeler Limited | Wood Group | oilfield services and supplies | bribery | 2021 | UK-SFO | £103,000,000 |
| Petrofac Limited | Petrofac Limited | oilfield services and supplies | bribery | 2021 | UK-SFO | £77,034,625 |
| BP Oil UK Limited | BP | oil and gas | price-fixing or anti-competitive practices | 2012 | UK-OFT | £0 |
| Mercedes-Benz UK Limited and Daimler UK Limited and Daimler AG | Mercedes-Benz Group | motor vehicles | price-fixing or anti-competitive practices | 2013 | UK-OFT | £1,492,646 |
| Heathrow Airport Ltd. and Heathrow Airport Holdings Ltd. | Heathrow Airport Holdings | miscellaneous services | price-fixing or anti-competitive practices | 2018 | UK-CMA | £1,600,000 |
| Royal Mail Group plc | International Distributions Services PLC | miscellaneous services | price-fixing or anti-competitive practices | 2019 | UK-OFCOM | £0 |
| Royal Mail plc | International Distributions Services PLC | miscellaneous services | price-fixing or anti-competitive practices | 2018 | UK-OFCOM | £50,000,000 |
| Experian Ltd | Experian | miscellaneous services | price-fixing or anti-competitive practices | 2011 | UK-OFT | £0 |
