Under Review: 
No Review
Date Breach Made Public: 
January 1, 2010
Los Gatos , CA
United States
California US
Records Breached: 

100 million not added to total

Breach Total Number: 
Year of Breach: 
Type of organization: 
Type of breach: 

A class action suit was filed against Netflix, Inc., in United States District Court for the Northern District of California. Plaintiffs in the suit are claiming that Netflix has “perpetrated the largest voluntary privacy breach to date.” According to the Complaint, Netflix knowingly and voluntarily disclosed the sensitive and personal information of approximately 480,000 Netflix subscribers when Netflix provided participants in a contest initiated to improve Netflix’s movie recommendation systems with data sets containing over 100 million subscriber movie ratings and preferences. Netflix has claimed that the data sets provided to the contest participants were anonymized and that the subscribers’ movie ratings were accompanied only by “a numeric identifier unique to the subscriber” (as opposed to the subscriber’s name or other personal information). However, the complaint cites the results of several researchers who, in fact, were able to crack Netflix’s anonymization process and identify individual subscribers.