BT's covert trial of Phorm's ISP adware technology in summer 2007 involved tracking many thousands more customers without their knowledge than previously reported, it's emerged.
Erroneous reports earlier this month suggested that a total of 36,000 broadband lines had been eavesdropped upon during the two trials. The Register had revealed that 18,000 customers were profiled in 2006, but no figure was released for the second experiment.
Today Phorm said the 2007 trial was actually performed on "tens of thousands" of lines. It refused to provide a specific figure, but at the absolute least there are 38,000 BT Retail customers unaware their communications have been allegedly criminally intercepted in the last two years. The number could be as high as 108,000.
We asked a Phorm spokesman why it doesn't believe people have the right to know how likely it is they were part of a secret test. "We're just not going to disclose that," he said. "They were BT customers and you have to ask BT about that."
A BT spokesman refused to provide a figure.
Phorm's 2006 financial report, dated 24 April 2007, states that it was about to begin a trial with "hundreds of thousands" of ISP customers. The firm was referring to its second trial with BT, which took place in June of that year, and was immediately denied by the national telco.
BT's spokesman said the experiment was scaled back from hundreds of thousands because "that's how it panned out".
Phorm sent us this statement:
We confirmed in our 2006 Financial Statement that we had concluded the trial announced on 19 July 2006 and were about to start a larger trial in 2007. In reality, the 2007 test was actually smaller than was planned at the point this statement was issued. At its peak, it involved tens of thousands of users for a couple of days, not the several hundred thousand as anticipated.
Don Foster MP, a Liberal Democrat who has taken a lead in parliament over the Phorm controversy, has called on BT to reveal the details of its allegedly illegal action. Branding BT's role in the secret trials "disgraceful", he said: "It's time for BT to come clean about exactly what happened last summer and why customers were kept in the dark while they were used as guinea pigs."
Instead, Emma Sanderson, the BT Retail executive offered to television news for interviews last week parroted the line that no personally identifiable information had been disclosed. She said the tests were "small scale".
BT has claimed that it has no way of telling which of its customers it Phorm profiled and served targeted advertising to. However, it's known that people in Weston-super-Mare were among those co-opted into BT's bid to gouge extra advertising revenues from their broadband subscription. Documents seen by The Register suggest that Phorm tests were performed at exchange level.
Phorm and BT say their lawyers told them the trials were legal, but won't say why.
A third trial is imminent, on 10,000 lines. BT says it's going to ask this time. ®