The Federal Trade Commission should scrutinize companies that engage in digital "fingerprinting" -- which involves tracking users based on the characteristics of their devices -- the advocacy group Center for Democracy & Technology says.
"There are not currently any privacy enhancing technologies that fully mitigate fingerprinting," the rights group says. "It is clear that this type of unregulated ... tracking represents a real danger not just to privacy, but the Internet itself."
The CDT submitted its comments in advance of an upcoming FTC workshop about the privacy issues raised by tracking consumers across devices for ad purposes. Some ad companies that link people's activity on smartphones and tablets with their activity on desktops accomplish this via "fingerprinting" technology.
That method is considered "probabilistic," because it depends on making inferences about users based on factors like their IP addresses, device types and browser settings. But even though the method might not be 100% accurate, it's still troubling to privacy advocates, given that consumers typically can't prevent companies from collecting that type of data.
Consider, in July, the World Wide Web Consortium came out against against digital fingerprinting, which it condemned as "a blatant violation of the human right to privacy."
The other major cross-device tracking method relies on compiling data about users who are logged in to sites or services.
The CDT says both forms of cross-device tracking -- by log-ins or by probabilistic methods -- can be problematic.
"Users are often unaware of the wealth and detail of information that is being collected about their online and offline activities and the significant privacy invasions that result," the group says.
The organization says that companies engaged in cross-device tracking should be "transparent" to users, and also allow consumers to wield control over whether data about themselves is collected.
"If companies cannot provide a meaningful way to notify users of data collection and give users the opportunity to decide what, if any, data is collected about them, then the FTC should examine whether this is an unfair process," the CDT says.
The Interactive Advertising Bureau also weighed in with the FTC. The trade group says the FTC should refrain from calling for new restrictions on companies' ability to collect data. "Rather than moving toward a prescriptive model of privacy regulation, which could limit companies’ ability to innovate, the FTC should continue its dialogue with industry and support for self-regulatory frameworks," the IAB writes.