Facebook employees discussed Cambridge Analytica as harvesting ignorant users' data as early as September 2015, months before any disclosure on the exercise, which later became one of the biggest scandals in the disrupted tech giants to date.
The information comes as part of a lawsuit filed by Washington D.C.'s Attorney General Karl Racine, who sues the social media giant for "ongoing illegal trading practices."
Facebook has moved to reject the case as well as keeping a key document sealed.
The sealed document, described in a lawsuit from Racine's office on Monday, includes "an email exchange between Facebook employees discussing how Cambridge Analytica (and others) violated Facebook's policies," the archive said. It also appears that data from "nearly half of all DC residents were swept up in this illegal sale" of data from Cambridge Analytica.
Facebook confirmed internal scratch calls and Cambridge Analytica described in the document, but called it "speculation" among employees in an email to ABC News.
"These were two different events: in September 201
Kogan refers to Aleksandr Kogan, the University Hospital of Cambridge who developed the question that gathers data from Facebook users. The results were then passed on to Cambridge Analytica.
The two sides met in court on Friday afternoon and DC Supreme Court Judge Fern F. Saddler said she would settle at the end of April to dismiss the case. She did not make a decision to unsealing the Facebook documents.
The messages between employees in September 2015 are "sincere employee reviews that several third-party applications have access to and sold consumer data in violation of Facebook's guidelines during the presidential election in 2016," according to Racine's submission. "It also indicates Facebook knew about Cambridge Analytics erroneous data collection practices months before news was reported on the problem."
The timing is important because the Cambridge Analytica scandal first revealed the public how tech companies share user data and how the data could have affected world events, especially the 2016 US elections and Brexit.
In December 2015, a report by the Guardian revealed that Cambridge Analytica, a political consulting firm that has since subsided, had gotten the data from tens of millions of people from Facebook by consulting company Global Science Research (GSR), a data-focused marketing firm employed of the Ted Cruz campaign.
GSR transferred this data without Cambridge's knowledge to Cambridge Analytics parent company Strategic Communications Laboratories (SCL). At that time, Steve Bannon was vice president of Cambridge Analytica. He then became the Donald Trumps 2016 campaign chair.
In March 2018, The Guardian published an explosive report describing how Cambridge Analytica opened the data from 50 million Facebook users. The number of users who were violated climbed later to 87 million. Cambridge Analytica had also been hired to work on the Trump campaign.
At the time of The Guardian Scoop, the ABC News campaign reported that it never used Cambridge Anaytica's data and said it was dependent on election information gathered by the Republican National Committee.
"Any allegations that voter data were used from another source to support the victory in 2016 are false," said Trump's Mayor.