"The ICO is clear that this information should never have been collected in the first place and the company's failure to secure its deletion as promised is a cause for concern, " the ICO said.
At Entrustet, another website that allows customers to appoint a digital executor to oversee the transfer and deletion of the deceased's web accounts, business is also growing at a healthy but modest rate.
Mr Coulson will now be pressed to disclose whether he was aware of the alleged interception and deletion of voicemail messages left on Milly Dowler's phone.