Think You’re Safe Storing or Releasing “Anonymized” Data? Think Again.

Anonymity is increasingly difficult to safeguard, and direct marketers that collect, maintain, share, and use customer information should take note of a recent class action settlement by Netflix than stemmed from the company's disclosure of an "anonymized" customer database.

Most federal and state privacy and data security statutes focus on the protection of "personally identifiable information," such as names, addresses, telephone numbers, financial account numbers, social security numbers, and email addresses. In response to such laws, many companies strip personally identifiable information from databases containing sensitive information. Once stripped of identifiers, the theory goes, the risks of identity theft or violations of consumer privacy rights resulting from disclosure of the data (whether purposeful or not) are eliminated. Some companies may even conclude that the data may be shared for marketing or "data mining" purposes without violating their privacy policies or applicable laws.

According to the Electronic Privacy Information Center, however, "computer scientists have revealed that this 'anonymized' data can easily be re-identified, such that the sensitive information may be linked back to an individual."