Ever heard of AcurianHealth? If you are in the US, you may get a letter for one of their research studies or drug trials based upon your prescriptions, your shopping habits, or your internet browsing. Where do they get that data? Quite legitimately, based on consent, Walgreens Boots will mail invitations for studies organized by Acurian to their pharmacy customers, where the user identification is withheld from Acurian. The privacy policy by which Walgreens does business with you permits this type of contact with you. These letters direct users to a generic sounding website for the study–and then life gets interesting. A visit to the site, whether from a letter, a search, or an online ad, may capture your information. There’s a bit of code from a company they work with, NaviStone, that captures information from partial or unsent information requests or signups. NaviStone then matches it up with what you think is anonymous behavior with other databases, and voilá, mail is sent to you via their ‘proprietary technology.’ Acurian uses databases from large data broker/aggregators like Epsilon and cranks away. It’s creepy behavior that stretches the definition of privacy and consent. Not reassuring is that Acurian has a database of over 100 million people who are supposedly opt-ins. How a Company You’ve Never Heard of Sends You Letters about Your Medical Condition (Gizmodo) Hat tip to Toni Bunting