Failure pattern · United States · 2014–2019
Facebook and Cambridge Analytica: a data scandal and a $5 billion fine
Data from up to 87 million Facebook users was harvested through a quiz app and used by a political consulting firm. The scandal led to congressional hearings and a record $5 billion FTC fine.
By Shivam Bhandari · Reviewed 31 October 2026 · How we write
by the numbers
- Users whose data was affected
- up to 87 million
- Quiz takers
- about 270,000
- FTC fine (2019)
- $5 billion
What happened
In 2014 a researcher built a personality quiz app on Facebook. About 270,000 people took the quiz, but Facebook's rules at the time let the app collect data on their friends too, ultimately covering up to 87 million people. The data was passed to Cambridge Analytica, a political consulting firm.
In March 2018 reports by The Guardian and The New York Times revealed the story. #DeleteFacebook trended, and Mark Zuckerberg testified before the US Congress in April 2018. Facebook tightened developer data access.
In July 2019 the US Federal Trade Commission fined Facebook $5 billion, at that time the largest privacy penalty ever, and required new oversight. The scandal permanently changed how regulators and users viewed social media data.
Timeline
- 2014
Quiz app collects friends' data.
- 2015
Facebook restricts friend data access.
- 2018
Scandal reported; Zuckerberg testifies.
- 2019
$5 billion FTC settlement.
what went wrong
- Platform rules prioritised developer growth over user privacy.
- Weak enforcement after data left the platform.
- Slow, minimising early response.
the lesson
Customer data is a trust liability as much as an asset — loose rules can create scandals years later.
Apply it to your business
- 1Collect only the customer data you really need.
- 2Know where customer data goes when shared with partners.
- 3Treat privacy as part of the product, not just compliance.
Laws at work in this story
Figures are rounded and drawn from public reports, company filings and widely cited coverage at the time. Check the company's latest filings before relying on any number.