authorized the app. we also required developers to get approval from us before they could request any sensitive data from people. these actions would prevent any app like kogan's from being able to access so much data today. in 2015 we learned that the journalists at the guardian that kogan had shared data from his app with cambridge analytica it is against our policies for developers it to share data with people's consent so we immediately banned kogan's app from our platform and demanded that kogan and cambridge analytica formally certificate that they had deleted all improperly acquired datea. they provided these certifications. last week we learned from the guarda the new york times and channel 4 that cambridge analytica may not have deleted the data as they had certified. we immediately banned them fromuation any of our services. they claim they have deleted the data and has agreed to a forensic audit by a firm we
to third parties -- this is the game facebook is in. if you don't have that, you don't have facebook. what's so sort of complicated and what makes that statement necessarily so long and so sort of conv. luted is that he is trying to maintain a company that is always vulnerable and has been vulnerable from the beginning to the kind of exploitation we saw by dr. kogan and cambridge analytica. he can reduce outside parties' ability to access that data, try to come up with penalty for those who break rules but trying to prevent this from happening 100% is not possible as long as facebook is facebook. >> as a facebook user, you go through the whole privacy, two-step verification. to think i may not have taken this personality quiz but one of my friends may have taken it and, therefore, my information,
more apps should be social. your calendar should be able to show your friend's birthdays, your maps should show where your friends live and your address book should show their pictures. we enabled people to log into apps, share who their friends were and some information about them. in 2013, a cambridge analytica -- rather cambridge university researcher aleksandr kogan created a personality quiz app. it was install bid 300,000 people who shared their data as well as some of their friends' data. given the way our platform worked at the time this meant kogan was able to access tens of millions of their friends' data. in 2014 to prevent abusive apps we announced that we were changing the entire platform to dramatically limit the data apps could access. most importantly apps like kogan's could no longer ask for data about a person's friends unless their friends had also
hired to confirm this. we're also working with regulators to investigate what happened. this was a breach of trust between kogan, cambridge analytica and facebook. but it was also a breach of trust between facebook and people who share their data with us and expect us to protect it. we need to fix that. in this case we already took most important step a few years ago in 2014 to prevent bad actors from access people's information in this way. but there's more we need to do. i'll outline those steps here. first we will investigate all apps that had access to large amounts of information before we changed to platform dramatically reduce data access in 2013, and we will conduct a full audit of any app that suspicious activity. we will ban any developer from our platform that does not agree to a thorough audit. if we find developers that misused personally identifiable information we will ban them and tell everyone asked by those apps. that includes people whose data kogan miss used here as well. second, we will restrict