The Cambridge Analytica scandal is wildly confusing. This timeline will help

Gather round for the tale of harvested Facebook data.
Gather round for the tale of harvested Facebook data.
Image: AP Photo/Noah Berger
We may earn a commission from links on this page.

Since the Cambridge Analytica scandal broke, one question has been on everyone’s minds:

So what happened, exactly?

This timeline is Quartz’s attempt to offer a comprehensive, yet clear, explanation of how Cambridge Analytica came to use the data of 50 million Facebook users, collected without their permission, to target potential Trump voters during the 2016 US presidential election. We’re also tracking the ongoing fallout from the scandal, which has engulfed Facebook and its CEO Mark Zuckerberg in an unprecedented backlash.

We’ll continue updating the timeline as more information comes out. For more information about a given event, just click on the bubble at the end of each sentence.


Facebook launches the first version of Open Graph API, which allows outside app developers to access user data. 1


The US Federal Trade Commission and Facebook sign a consent decree in which the company promises it won’t share users’ data without their permission. 2.


UK-based Strategic Communication Laboratories Group (SCL) founds Cambridge Analytica as its US arm for operations. The move is orchestrated by alt-right publisher Steve Bannon. 3


Cambridge Analytica gets data on Facebook users from Cambridge University researcher Aleksandr Kogan, in violation of
Facebook’s terms. 4

Cambridge Analytica works on the 2014 midterm elections. 5

Christopher Wylie, a data scientist who helped build Cambridge Analytica and would go on to be the key whistleblower in the scandal, leaves the company in July.

Facebook starts to change its policies on using people’s data. 6


Wylie, who started his own company after leaving Cambridge Analytica, still has the harvested Facebook data in his possession—but he says he deletes it sometime in 2015. 7


Wylie’s company, Eunoia Technologies, meets with Donald Trump’s campaign operative Corey Lewandowski to discuss microtargeting techniques. 8


Bloomberg reports that the pro-Brexit campaign group Leave.EU, headed by Nigel Farage, has hired Cambridge Analytica 9


A report in The Guardian shows that Republican presidential nominee Ted Cruz had hired Cambridge Analytica 10


After the Cruz campaign folds, Cambridge Analytica is hired by Donald Trump’s presidential campaign. 11

AggregateIQ, a Canadian firm employed by SCL Group that was reportedly referred to internally as a branch of Cambridge Analytica, is hired by the other major pro-Brexit group, Vote Leave. 12

Both Trump and the “Leave” faction win their respective votes.


Special counsel Robert Mueller requests files from Cambridge Analytica in relation to Russian interference in US presidential election, The Wall Street Journal reports. 13



Blockbuster reports from The New York Times and The Observer show that the scale of the data harvesting by Kogan and Cambridge Analytica was much bigger than previously thought. 14

Cambridge Analytica is in a lot of trouble. Its executives are caught on tape boasting about using shady and illegal practices in their work in multiple countries. 15

After days of silence, Mark Zuckerberg finally responds to the scandal. 16

Lawmakers demand Facebook explain itself, while regulators and other officials launch investigations into its actions. The company also faces a boycott from users, and anxiety from investors. 17

Michael Coren contributed to this story.