Information is information and the more you have, the easier it is to figure out where it came from. Some data makes it easier than others.
I worked with a hospital awhile back with patient radiological data (for free and for science). Patients had to explicly sign-off that they were sharing their data with us and what we planned to use it for. A lot of the metadata from DICOM wasn't even wiped, I had their names, street addresses, all sorts of stuff which was supposed to be wiped (de-identified).
Even then, I worked with data from a patient with a brain tumor and their neurosurgeon looking to remove it. That data was correctly anonymoized but it was their head, so I could basically reconstruct their face--so is a coarse geomerric sampling of a face de-identified? I guess it depends on how coarse it was.
Just look at what's done with social media, advertising, and browser data to get an idea of where things can go.
I worked with a hospital awhile back with patient radiological data (for free and for science). Patients had to explicly sign-off that they were sharing their data with us and what we planned to use it for. A lot of the metadata from DICOM wasn't even wiped, I had their names, street addresses, all sorts of stuff which was supposed to be wiped (de-identified).
Even then, I worked with data from a patient with a brain tumor and their neurosurgeon looking to remove it. That data was correctly anonymoized but it was their head, so I could basically reconstruct their face--so is a coarse geomerric sampling of a face de-identified? I guess it depends on how coarse it was.
Just look at what's done with social media, advertising, and browser data to get an idea of where things can go.