Ofgem has revealed it has launched an investigation into both United Gas and Power and Shell-owned Hudson Energy Supply.
The energy regulator says the investigation seeks to clarify whether non-domestic supplier United breached rules around billing, meter reading and communications.
A spokesperson told Utility Week Ofgem was made aware of the issues last month and added that neither company has been subject to investigations previously.
Ofgem added Leeds-based United has acted on behalf of Hudson Energy Supply since 2013 and therefore Hudson is responsible for the actions of United Gas and Power in relation to customers supplied under its supply licences.
The regulator said further details of the investigation cannot be made public at this point.
A spokesperson for Shell said the investigation relates to the period before it acquired Hudson. They added: “We continue to cooperate fully with Ofgem and will support them in their investigation.”
Ofgem stressed that the opening of the investigation does not imply it has made any findings about non-compliance by United Gas and Power or Hudson Energy Supply.