An article in the New York Times (May 16,2013) describes software that uses insurance records, claims etc to track individual drug prescriptions from doctors to patients to pharmacies, including refills, albeit without patient identifiers. But the data does include details such as income and ethnicity. Pharmaceutical companies claim that this helps them target potential demand sources, offer more efficient alternatives, identify interactions across doctors based on patient and other flows to target market their products etc. But is the data so refined that individual patient histories will now become available to pharmaceutical companies and if so, is there an implied worry ? Will more targeted marketing lower pharmaceutical company costs and thus lower drug costs and help the patient ? More generally, is there a benefit to the supply chain as a whole (costs or efficacy) if detailed usage data becomes available ?