[ctrl-j]

Only because they capture a lot of data and keep the row level information.

If you just grabbed clustered coordinates without any device information there wouldn't be enough data to be able to reconstruct identity information.

[Cpoll]

There's a lot of ways it can go wrong though:

- If they provide a unique ID with each coordinate. Now you can deanonymize by correlation

- If they provide a coordinate for every used in the system. Now you know where everyone is

- From the above, if the data is presented in frequent intervals, you can correlate coordinates with last know coordinates and start drawing paths

I'd be comfortable if the request is "give us a coordinate for every area that has more than N users in it" for some large N. Filtering out apartment buildings shouldn't be too difficult.

[zelphirkalt]

> every useD in the system

Funny typo, or perhaps not? Reminds me of Stallman talking about Facebook and switching out "users" with "useds".