IMHO the DNA study is sort of a red herring. The real story here is that ZIP code, birthdate and gender have enough bits of entropy between them that they can uniquely identify people 40% of the time.<p>I personally usually fill out my birthdate as January 1 of the nearest year that is evenly divisible by 10 [1].<p>[1] Mainly when registering a new account with some random website that makes you type in your date of birth to register an account. If it's connected to my finances, employment, or medicine, of course I give them the real deal. Of course, thanks to my wonderful government, even this may be a felony [2].<p>[2] <a href="https://www.eff.org/deeplinks/2013/04/are-you-teenager-who-reads-news-online-according-justice-department-you-may-be" rel="nofollow">https://www.eff.org/deeplinks/2013/04/are-you-teenager-who-r...</a>