incident · 1521244800000

Facebook-Cambridge Analytica Data Scandal

Whistleblowers revealed that Cambridge Analytica harvested personal data from up to 87 million Facebook users without their consent for political advertising purposes.

What happened

A third-party app collected data not only from users who took a personality quiz but also from their Facebook friends. This data was used to build psychological profiles for targeted political campaigns.

Technical mechanism

The data harvesting exploited Facebook's Open Graph API, which at the time allowed developers to access data from a user's friends network without explicit consent from those friends.

Why it matters

The scandal fundamentally changed public perception of data privacy, leading to intense regulatory scrutiny of social media platforms and their data sharing practices.

Impact

Exposed the data of millions of users, resulted in a $5 billion FTC fine for Facebook, and sparked global investigations into data privacy practices and political manipulation.

Response

Facebook restricted API access, apologized publicly, and faced congressional hearings. The FTC and other global regulators launched investigations and levied record fines.

Defensive lessons

  • Third-party API access must be strictly governed and monitored.
  • User consent must be explicit, informed, and limited to the stated purpose.
  • Data harvesting at scale poses significant risks to privacy and democratic processes.

Evidence register

  1. Federal Trade Commission — FTC Issues Opinion and Order Against Cambridge Analytica (verified)