Phorm admitted on Thursday that preparations for the first major trial of its internet advertising technology had taken “longer than originally anticipated” but that it still expected deployments to go ahead with the UK’s largest broadband providers.

Phorm’s technology is placed within internet service providers’ networks to monitor the sites visited by broadband users, in order to direct more appropriate advertising at them. Although Phorm said that the anonymity of broadband users is guaranteed, some consumer groups have expressed concern about a perceived invasion of privacy by tracking browsing behaviour.