Following Facebook CEO Mark Zuckerberg’s Congressional testimony last week, the site has again responded to claims of leaking users data. The two day long hearing covered topics such as privacy and data collection of non-users. Facebook product management director David Baser wrote in a Facebook Newsroom post,

“Twitter, Pinterest and LinkedIn all have similar Like and Share buttons to help people share things on their services,” wrote Baser. “In fact, most websites and apps send the same information to multiple companies each time you visit them.”

This post was designed to answer questions that Zuckerberg did not answer during the Congressional hearing on Facebook’s practice of selling users stored data to outside agencies. Baser also mentions how Facebook, as well as many other social media sites, use analytics to track their users data. The post then goes into explaining how analytics work for users of specific social sites, but a major issue that wasn’t addressed in the hearing was how Facebook tracks non-users. Zuckerberg was asked how “shadow profiles” of non users are used in order to target advertising to which he responded how this data is used to promote more relevant ads to users. There has been a great deal of controversy over how Facebook is sharing it’s non-users data. In the hearing it was not clarified over how exactly Facebook does this for non-users and with what tools.

Early Facebook user Julia Carrie Wong’s article on The Guardian discusses her disappointment with Facebook’s privacy policy over the past decade. Wong responded to Zuckerberg’s hearing she claims that he “sought to assure the public that we, not he, are in “complete control” of our relationships with Facebook.”

Facebook has responded to most of these data collection claims by stating that the data used from users browsing other sites to show more relevant ads. However, it was recently found that 87 million users data had been stored without their knowledge.