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Privacy is a casualty on Facebook

13 million in US don’t use site’s controls, according to investigation

joerg Koch/Associated Press

Nearly 13 million US Facebook users do not use, or are not aware of, the site’s privacy controls, according to a Consumer Reports investigation on Facebook and privacy. As a result, users are potentially exposing personal information beyond their network of Facebook friends.

The report also revealed that a projected 4.8 million people have posted about where they planned to go on a certain day, a potential tip-off to burglars, while 4.7 million have “liked” a Facebook page about health conditions or treatments, details that insurers might use against them.

The Consumer Reports investigation focused on Facebook because it is the largest social network with just over 900 million users worldwide and more than 150 million in the United States. The service makes it easy for people to keep up with friends, family, and colleagues, discover great content, and connect to causes. To deliver this service, Facebook and other social networks collect enormous amounts of often highly sensitive information and distribute it widely and quickly.

All of this data collection is not without risks. A projected 7 million households using Facebook said they had trouble last year, ranging from someone using their log-in without permission to being harassed or threatened — up 30 percent from the previous year, according to the Consumer Reports Annual State of the Net survey. And unless an individual has chosen their privacy settings meticulously, a friend who runs an app could grant it access to their information without their knowledge, including information that was set to “friends only” view. Only 37 percent of users say they have used Facebook’s privacy tools to customize how much information apps are allowed to see, according to the Consmer Reports survey.

For its part, Facebook says it takes privacy and safety issues seriously. Chief executive Mark Zuckerberg has said that the company does privacy access checks tens of billions of times each day.

Nine ways to stay protected

Facebook offers many privacy controls that may not be easy to understand. Below are nine tips from Consumer Reports that will help users understand and utilize privacy tools:

Think before typing. Even if a user deletes his or her account (which takes Facebook about a month), some info can remain in Facebook’s computers for up to 90 days.

Regularly check Facebook exposure. Each month, check out how the page looks to others. Review individual privacy settings if necessary.

Protect basic information. Set the audience for profile items, such as town or employer. And users should remember: Sharing info with “friends of friends” could expose them to tens of thousands.

Know what can’t be protected. Each user’s name and profile picture are public. To protect one’s identity, they should not use a photo, or use one that doesn’t show their face.

“UnPublic” the wall. Set the audience for all previous wall posts to just friends.

Turn off Tag Suggest. If users would rather not have Facebook automatically recognize their face in photos, they could disable that feature in their privacy settings. The information will be deleted.

Block apps and sites that snoop. Unless users intercede, friends can share personal information about them with apps. To block that, use controls to limit the info apps can see.

Keep wall posts from friends. Users don’t have to share every wall post with every friend. They can also keep certain people from viewing specific items in their profile.

When all else fails, deactivate. When a user deactivates their account, Facebook retains profile data, but the account is made temporarily inaccessible. Deleting an account, on the other hand, makes it inaccessible forever.

Consumer Reports writes columns, reviews, and ratings on cars, appliances, electronics, and other consumer goods. Previous stories can be found at consumerreports.org.