Targeted advertising hits emergency rooms

Patients sitting in emergency rooms, at chiropractors’ offices and at pain clinics in the Philadelphia area may start noticing on their phones the kind of messages typically seen along highway billboards and public transit: personal injury law firms looking for business by casting mobile online ads at patients.

The potentially creepy part? They’re only getting fed the ad because somebody knows they are in an emergency room.

The technology behind the ads, known as geofencing, or placing a digital perimeter around a specific location, has been deployed by retailers for years to offer coupons and special offers to customers as they shop. Bringing it into health care spaces, however, is raising alarm among privacy experts.

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