The Opt-In Hoax
Phorm were instructed in April 2008 by the Information Commissioner to implement an 'opt in' subscription model. (source)
An opt in model of operation requires a voluntary action on the part of a person to receive a service.
So let's see if they are operating a voluntary opt in model...
There are two parties to the communication being intercepted, a consumer, and a content owner. Lets deal with each separately.
Content owners are not asked to opt in to profiling.
Their content and communications are used without explicit consent, or a copyright licence in advance, as required by UK law.
Phorm provide an opt out... but opting out is illegal.
The content owners who do request to opt out find their web site is immediately scraped for keywords. After requesting exclusion, sites are visited by the following sources; Phorm Moscow Russia/Hosting Telesystems Network (188.8.131.52), Phorm London UK (184.108.40.206 / 220.127.116.11), Optimum Online USA (18.104.22.168), Verizon Internet Services USA (22.214.171.124) and British Telecommunications London UK (126.96.36.199).
Phorm inject an 'invitation' page into a consumer's web traffic.
From the first time you are confronted with the unexpected invitation to participate, you are being involuntarily intercepted by your ISP. BT's 'customer choice' diagram makes it clear; there is no way to bypass Phorm.
Consequently customers who do not wish to participate in Phorm are compelled to retain and present a cookie with each and every request which includes the value 'OPTED_OUT'; (source)
This cookie must be presented by each application, by each user, on each computer that you own.
Being forced to "opt out" is clearly not an "opt in" model.
Contrary to their assertions, Phorm is not an "opt in" service, for consumers or content creators.
If you don't wish to participate as a content owner, you have no choice, your communications will be involuntarily harvested for marketing intelligence.
If you don't wish to participate as a consumer, you have no choice, you must involuntarily retain an opt out cookie.
Actually you do have a choice; move to a new Phorm free ISP.