Fitness app releases data-set that reveals the location of sensitive military bases, patrol routes, aircrew flightpaths, and individual soldiers' jogging routes

Strava is a popular fitness route-tracker focused on sharing the maps of your workouts with others; last November, the company released an "anonymized" data-set of over 3 trillion GPS points, and over the weekend, Institute for United Conflict Analysts co-founder Nathan Ruser started a Twitter thread pointing out the sensitive locations and details revealed by the release.

Because Strava is used by military personnel — including pilots, who appear to leave it running while they are flying on military missions — the data shows the locations of military bases (including some that were heretofore secret) around the world. The data reveal the individual routes run by military personnel overseas, and isolate individual routes between sparsely located houses.

There is probably more to be found in the data. A time-series would reveal still more.

It's an excellent cautionary tale about the risks of re-identification attacks. It would be really, genuinely useful and beneficial if there was a way to de-identify large data-sets and make them available for study, innovative new uses, and scientific research, but wanting it badly is not enough. Regrettably, there's plenty of policy that starts from the principle that we need de-identified data and the proceeds to say, "Once your data has been de-identified to the standard of industry best practices, you can do whatever you want with it." This faith-based policy-making creates an industry-sized loophole in the otherwise excellent and comprehensive European General Data Protection Regulation.

It's important to keep stories like this in mind when we have these policy discussions that assume that there is such a thing as de-identification.

Strava released their global heatmap. 13 trillion GPS points from their users (turning off data sharing is an option). … … It looks very pretty, but not amazing for Op-Sec. US Bases are clearly identifiable and mappable [Nathan Ruser/Twitter]

Fitness tracking app Strava gives away location of secret US army bases | Technology [Alex Hern/The Guardian]