[richlevy]

It's bad enough worrying about law enforcement misusing data, but stuff like this makes you wonder if anyone 'gets it'.

The suit is also asking the court to stop Netflix from launching its promised second contest to improve the recommendations — this time giving out user data that includes ZIP codes, ages and gender, along with movie ratings and ID numbers substituted for user names.
That’s a foolish idea on Netflix’s part, according to University of Colorado law professor Paul Ohm, who in a blog post in September called the idea “a privacy blunder that could cost millions of dollars in fines and civil damages.” Ohm, a former Justice Department lawyer, recently authored a legal paper calling into question the practice of anonymizing data, essentially finding that if data is useful to researchers, it could also, by definition, be re-identified.
For instance, if a data set reveals a person’s ZIP code, birthdate and gender, there’s an 87 percent chance that the person can be uniquely identified.

So figure theres 20,000 people in a zip code, half of them (10000) are either male or female and there's 13,514 birthdays between an 18-year-old and a 55-year-old. So yeah, knowing those 3 things could let you zero in on someone.

So if some social site or credit bureau were to sell name, birthday, and zip code, it could be matched to the 'anonymous' Netflix data to reveal a persons movie rentals, information that is protected by law.