SAN FRANCISCO (KPIX 5) — Mark Zuckerberg faced another round of questioning from lawmakers on Capitol Hill Wednesday and the Facebook CEO revealed that the company tracks people even if they don’t have an account.

On Tuesday, Zuckerberg was asked what data they collect after people have logged out, and he couldn’t answer.

But on Wednesday he was asked again, and he was able to answer, but the truth may surprise you.

“Americans don’t like being manipulated,” said Rep. Kathy Castor (D-FL).

Matt Stoller is a fellow at an anti-monopoly think tank and said, “That’s what this is really about.”

Stoller says there’s something unsettling about Facebook’s data collection.

“There’s a strong element of privacy questions, a sort of creepiness vibe, because Facebook is a surveillance machine,” Stoller said.

We learned Wednesday that it goes far beyond what you post on the site.

The company collects data on anyone who visits the website, even if they don’t have an account.

Rep. Castor said, “They track you. You’re collecting medical data, correct, on people that are on the Internet, whether they’re Facebook users or not, right?”

Zuckerberg’s responds, “Congresswoman, yes, we collect some data.”

And because Facebook claims it’s for security, there’s no way to turn it off.

Zuckerberg said, “For obvious reasons we do not allow people to turn off the measurement that we do around security.”

Zuckerberg couldn’t say what data they keep for non-users.

Rep. Ben Ray Lujan (D-NM) asked Zuckerberg, “Do you know how many points of data that Facebook has on the average non-Facebook user?”

Zuckerberg replied, “Congressman, I do not off the top of my head, but I can have our team get back to you afterwards.”

Not only that, whether you have a Facebook account or not, if you visit a website with a Facebook like or share button on it, or one that has hidden Facebook code, the company is collecting data. Even if you don’t click the like or share button.

Rep. Debbie Dingell (D-MI) said, “Here’s what I do know: you have trackers all over the web. On practically every website you go to we all see the Facebook “like” or Facebook “share” buttons…It doesn’t matter whether you have a Facebook account. Through those tools, Facebook is able to collect information from all of us.”

Stoller says lots of marketing companies collect data, but Facebook is different. It’s as if the owner of the phone company could also listen to your conversations.

Stoller said, “It’s not just the tracking, it’s the ability to manipulate people with that tracking, and the inability to avoid it because these are essential communications services.”

Some ad blockers and browsers, like Firefox, have recently made products specifically designed to prevent Facebook tracking.

The Federal Trade Commission has power to fine the company millions of dollars or even break up Facebook.

The FTC is investigating Facebook and on Wednesday, while the House was hearing from Zuckerberg, the Senate was vetting a candidate to be a commissioner on the FTC. The candidate got a lot of questions about Facebook, indicating to many that Facebook is likely to be a priority going forward.

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