OnStar will track you even if you cancel service

For years, General Motors' OnStar service has been a stoic electronic nanny, there to help if your car's crashed or stolen, but otherwise pleasantly unobtrusive. Now OnStar wants the right to sell data about GM owners' driving habits — even if they've canceled the service.

The changes were caught by several eagle-eyed subscribers who received notice of an updated terms of service from OnStar last week. OnStar has always been able to track a subscriber's location, among other things, with its built-in GPS chip in case of emergency, but the new terms of service spell out that OnStar will keep logging data about a vehicle even if the subscriber cancels service or sells the car. The only way to kill the data link is by specifically telling OnStar to shut it off.

The other change that's causing concern was OnStar's admission that for the first time, it would consider selling GPS data about its customers to marketers or other businesses, with no prior approval of OnStar subscribers. It vows that such data will be "anonymized;" OnStar executives have spoken in the past about trying to use aggregate driving data as a trend-spotting service for businesses and government agencies.

Jonathan Zdziarski, an OnStar customer and forensic scientist, said the changes were enough for him to cancel:

It's impossible to anonymize GPS data! If your vehicle is consistently parked at your home, driving down your driveway, or taking a left or right turn onto your street, its pretty obvious that this is where you live! It's like trying to say that someone's Google Map lookup from their home is "anonymized" because it doesn't have their name on it. It still shows where they live! What's unique even more-so to OnStar is that the data they claim they sell as part of their business model is useless unless it's specific; that is, not diluted to the nearest 10 mile radius, etc. This combination of analytics, and their prospective customers (law enforcement, marketers, etc) requires the data be disturbingly precise.

OnStar chief spokesman Vijay Iyer says the response has been overblown, and that OnStar has no deals in place to sell data. OnStar wrote the changes to give it room for future possibilities, and that it would only give out broad measurements of driving habits — such as how many OnStar-equipped cars were on a particular freeway at a given time. "We're not drilling down to the personal data of an individual," he said.

The changes so far apply only to GM vehicles with OnStar built-in, not the units OnStar began selling last year for other makes. But given the company's mandate from GM to grow, it's clear the people behind the blue button want to do a bigger job than just nannying.