The Center for Democracy and Technology (CDT) has filed comments with the Network Advertising Initiative, an industry group that sets guidelines for advertising based on member recommendations, regarding ISPs desire to serve behaviorally targeted ads to users.

The CDT stated that internet service providers (ISPs) must collect the consent of customers before serving them ads based on their online activities. Furthermore, the consumer opt-in process must be "unavoidable … and affirmative."

US and UK ISPs typically have to work with a third party to serve advertising to users. Some services, like NebuAds, enable users to opt out; others, like the UK's Phorm, are planning opt-out capabilities.

But "opt-out" buttons suggest ISPs will serve ads by default: users must act if they want to be excluded. The CDI demands restrictions be made so that users must act if they want the ads in the first place, minimizing the pool of participation significantly.

Lawmakers are currently examining privacy concerns regarding ISP contributions to behavioral advertising at the Senate level.

Meanwhile, the Network Advertising Initiative is revising its privacy guidelines, which do not address behavioral targeting. In April, the Initiative did state that behavioral targeting should not take medical conditions into account.