Cambridge Analytica says the data it licensed from Global Science Research (GSR), which collected information on millions of Facebook users through a personality quiz app, was "ineffectual," an evaluation that prompted its decision to not use the data in Donald Trump's 2016 presidential campaign.
In a Tuesday press conference, Cambridge Analytica spokesman Clarence Mitchell said the company tested the data to see if it could improve the performance of advertising campaigns. The tests were conducted in 2014 and 2015.
The data was harvested by an app called This Is Your Digital Life, which was developed by Cambridge University lecturer Aleksandr Kogan. Kogan also founded GSR.
"Cambridge Analytica's research showed that the personality types licensed by the Kogan data underperformed when compared to more traditional ways of grouping people by demographics," Mitchell said.
Cambridge Analytica used data provided by the Republican National Committee and tapped commercially available data sources for the Trump Campaign, Mitchell said. It also used publicly accessible data, such as information from the voter registry.
Cambridge Analytica later decided to collect its own personality data through marketing research panels and interviews, Mitchell said. The respondents gave their full consent, he added.
Cambridge Analytica is in the midst of a data mining scandal involving the world's largest social network that has already been the subject of Congressional hearings. Facebook banned the UK-based political data analysis firm last month, saying Cambridge Analytica improperly received as many as 87 million user profiles leaked from the social network's service.
Facebook has said Kogan collected the data legitimately through the personality quiz but then violated its terms by passing the information along to Cambridge Analytica, which was later hired by the Trump presidential campaign.
Facebook didn't inform the public when it learned of the infraction in 2015, instead telling the parties involved to destroy the information. In Tuesday's press conference, Mitchell disputed reports that not all the data was deleted.
"Cambridge Analytica has cooperated fully with Facebook and immediately set about deleting all of the disputed data from its service, and has since carried out considerable work to make sure that none of its derivatives or any copies elsewhere or backups were left in the system," Mitchell said.
Facebook and Kogan didn't immediately respond to requests for comment.
On Sunday, Cambridge Analytica issued a statement saying that Kogan and GSR made a contractual commitment that the data was . Mitchell also reiterated during the press conference that the license was only for about 30 million respondents in the US.
Cambridge Analytica: Everything you need to know about Facebook's data mining scandal.
iHate: CNET looks at how intolerance is taking over the internet.