Users could also fall victim to the site’s business model. Like Sermo, PatientsLikeMe doesn’t sell advertising. Rather, the company earns its revenue through data-sharing partnerships with, for example, pharmaceutical and medical device companies. PatientsLikeMe’s own research teams have also utilized the site’s user-generated content. Although information sharing is limited to deidentified data, it poses new threats to patient privacy because sophisticated data mining and deanonymization techniques could reidentify people, even from such anonymous information.4,8 One concern is that targeted marketing could influence patients to seek drugs they don’t need or spend more money on branded drugs rather than generics. Moreover, employers or health insurers could gain access to a patient’s profiles, leading to potential penalties against the patient. Finally, the site doesn’t meaningfully disclose how the data is collected and used, although it gives its partners many patients’ digital profiles that can include conditions, concerns, fears,and behaviors.