At least until 2015, Facebook granted app developers liberal access to the data of Facebook users, and critics say that Cambridge was far from the only firm to harvest Facebook user data for dubious purposes.
The firm has worked with political groups all around the world - including US President Donald Trump's election campaign.
The company has seen its business practices heavily scrutinised in the wake of the Cambridge Analytica data privacy scandal.
Zuckerberg's comments signal that Facebook users in the USA may soon have less control over their personal data than European users.
Since March 16, when the news about Cambridge Analytica was disclosed, Facebook shares have fallen almost 18 percent.
Asked about the discrepancy between Facebook's estimate of the number of users affected and the widely reported figure of 50 million, a spokeswoman for the company said Facebook used "an expansive methodology" to arrive at 87 million. It is implementing these changes as part of a three-part plan to restrict data access. Although Facebook says the changes aren't prompted by recent events, it's an opportune time.
Facebook Inc Chief Executive Officer Mark Zuckerberg will testify next week before a congressional committee over a political consulting firm's misuse of customer data to interfere in the US presidential election, USA lawmakers said on Wednesday.
Zuckerberg is also doing a conference call with reporters Wednesday at 4 p.m. Several users were surprised to learn recently that Facebook had been collecting such data.
Facebook chief executive Mark Zuckerberg will testify in Congress next week over the hijacking of users' personal data by political consultancy Cambridge Analytica, a House committee announced Wednesday.
In an announcement Wednesday, Reps.
In a blog post, Facebook's Chief Technology Officer Mike Schroepfer said the company believes data from up to 87 million people was "improperly shared" with Cambridge Analytica, the consulting firm who received data on users and their networks from a researcher who developed an app that captured the information.
Walden, R-Ore., is the House Energy and Commerce committee's chairman.
Frank Pallone (D-N.J.) released a statement claiming the hearing, "will be an important opportunity to shed light on critical consumer data privacy issues and help all Americans better understand what happens to their personal information online".