Your browser history is for sale, here's what you need to know

What to know about Internet privacy changes
What to know about Internet privacy changes

It's official: Your browsing history can be sold to advertisers. President Trump on Monday signed a measure reversing rules that would have required internet providers to get consent before selling your browsing history.

The rules had not yet gone into effect, but providers now find themselves with new freedom when it comes to collecting and selling their customers' data. What does that mean for you?

What identifying information do they have?

Internet providers already collect a lot of information that's necessary to maintain their networks, like your location and what you're looking at online.

Many have said they will not use "sensitive" information, like medical records, children's data and banking details without consent. However a simple browsing history can reveal those personal details, such as symptoms you've Googled. There are concerns that it would be possible to identify people based on this detailed information.

Related: Congress just killed your Internet privacy protections

According to Dane Jasper, cofounder of Sonic, an independent ISP located in California, an internet provider can infer a lot about you based just on your browsing. In addition to basics like age and gender, they might know who your friends are, if you're a recovering alcoholic, or where you went to school. In theory, they could create an in-depth profile of you.

How will my information be used?

Internet providers will likely sell anonymized information to marketers and advertisers so they can better target ads.

Right now, it may seem like individual brands follow you around the web. After you look at boots on Zappos, advertisements from Zappos will likely appear on other unrelated websites. If a provider is collecting information about your behavior on multiple sites, a competitor could use it in real time to show you ads for rival shoe brands. You might also see ads that are more precisely targeted based on the deeper profiles that internet providers are able to build about you, even if they aren't connected to your specific identity.

Aggregated information about millions of customers would also provide insights into people's shopping habits. Do they usually check Amazon (AMZN) prices after looking at Walmart (WMT)? What else do they do online?

"This information could be packaged and sold to marketers who could use that information to develop a better understanding of how things are sold on the web," said Jasper.

Can they sell individuals' browsing information?

Collected information will mostly likely continue to be sold as anonymized data. But can an ISP sell a person's history with their name attached to it?

"It's not clear the law prohibits them from doing it," said Georgia Tech privacy expert Peter Swire.

Related: Worried about companies spying on your browsing? Here's what you can do

In fact, existing law requires telecommunications companies to protect the information of their customers, said Laura Moy, deputy director of the Center on Privacy and Technology at Georgetown Law. Therefore, she doesn't think the law would allow companies to sell the web browsing history of an individual person with their name attached to it.

Moy won't rule out the possibility entirely, though, because language in the existing law is murky.

"I could imagine a situation where they could sell browsing history and take out identifying information," she said. The problem is, "If someone really wanted to find you in that data set, they probably could."

Questions of legality aside, public backlash would be fierce, Swire noted. From a public relations standpoint, it's not in the best interests of big internet companies to sell individual browsing histories -- which makes it unlikely they will.

"It's not likely that we'll see carriers selling data to a dude with a Kickstarter," said Jasper.

Will this make it easier for police to get information on people?

The rules didn't address warrants to begin with, so there's unlikely to be a major change in how internet providers deal with law enforcement at this time.

Aren't Google and Facebook already collecting and selling my data?

The carriers' biggest argument for killing the rules was that companies like Facebook (FB), Google (GOOGL) and Netflix (NFLX) can already collect and sell information. Customers might be less concerned about this because it's an understood exchange. Google tracks browsing and scans Gmail to serve ads, and in exchange all of their services are free.

"The expectation is that within their silo, they learn about us and serve us ads and that's how they make their money," says Jasper. "But an internet provider, you pay them $50 a month or more. You're a subscriber, and to violate the trust of that subscriber ... to me it's just kind of creepy."

How can I protect my data?

There are many steps you can take to try and protect your browsing history. We've written a lot of words about that too.

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