Why do I need HIPAA-compliant geocoding?

Addresses, even if they are detached from patient names, are one of the 18 types of Personal Health Information (PHI) that are covered under HIPAA: "All geographical subdivisions smaller than a State, including street address, city, county, precinct, zip code, and their equivalent geocodes, except for the initial three digits of a zip code, if according to the current publicly available data from the Bureau of the Census:

The geographic unit formed by combining all zip codes with the same three initial digits contains more than 20,000 people; and, The initial three digits of a zip code for all such geographic units containing 20,000 or fewer people is changed to 000."

This means that if you are working with patient address data, you need a HIPAA-compliant geocoder.