Centrica, SSE, Npower, Eon and EDF claimed that the sharing of consumers data may not comply with data protection law and could erode trust in the industry.
Independents Ecotricity, Utilita and Good Energy also raised concerns that the remedy could be detrimental.
The suppliers submitted written responses to a draft order consultation on how the database sharing remedy from the Competition and Markets Authority (CMA) will be implemented.
In its letter, Centrica said: “We reiterate that we continue to have significant concerns regarding the manner in which consent from customers is sought for inclusion of their data in the database, and specifically the extent to which this is compatible with current and future data protection law.”
SSE added: “SSE would question whether the CMA’s proposal can be said to be compatible with both current and future data protection law (specifically the GDPR).”
Npower also said that the remedy “goes against” best practice guidance and allows suppliers to potentially “cherry pick” customers.
Eon called for reassurance from the ICO that the provision of relevant data and storage will meet requirements of all data protection legislation whilst EDF said the remedy risks resulting in a “poor customer experience”.
Ecotricity said it is “categorically against” the implantation of the remedy and Utilita said it has “serious concerns” and that the communication could be “intrusive”. Good Energy noted concerns about how consumers consent to their information being on the database.
The remedy was recommended in the CMA’s final report in June following a two-year probe into competition and engagement in the Energy market. An Ofgem-controlled database would allow suppliers access to information of consumers who have been on a Standard Variable Tariff for more than three years and send them postal marketing. If a customer does not wish to receive communications from energy providers, they must opt out of the service.