Is Facebook using your location data to suggest 'people you may know'?

Trying to understand Facebook's mysterious, ever-changing algorithm has become tantamount to searching for the meaning of life among power users.

Howdoes eachnewsfeedcome to be? Who or whatdeterminesthe posts you see,the ads you're served, and thepeople you're encouraged to connect with?

There aremany theories, but it's hard tosay for certainbecauseonly Facebookknows how Facebookreally worksand it keepsthe social network's recipe locked up tighter than the Colonel's(whichis likewise protectedas a "corporate trade secret" by KFC.)

As such, tech watchers were curiousthis week when rumours started swirling that a newcrack had formed in Facebook's carefully guarded veneer,revealingsomething we hadn't previously knownabout the network's suggested friends or"people you may know" feature.

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"While the magic sauce behind friend suggestions has always been a bit mysterious, it now includes some potentially unsettling information," reported Kashmir Hill forFusionon Monday. "Thanks to tracking the location of users' smartphones, the social network may suggest you friend people you've shared a GPS data point with."

If true, this means thatFacebook could suggest a"friend"to youbasedon whereyou've been and when, regardless of whether you've actually met them.

It also means that astrangercould seeyour face in their list ofrecommended contacts an idea that's creeping outprivacy advocates and casual users alike.

But is it more than an idea? Is Facebookreallyusing mobilelocation data to populate ourfriend request feeds?

According to a statementreleased by the company on Monday,yes, but only inpart.

"We often suggest people you may know based on things you have in common, like mutual friends, places you've visited, or the city you live in," reads the statement, which Fusion published on Monday."But location information by itself doesn't indicate that two people might be friends.That's why location is only one of the factors we use to suggest people you may know."

News that the social networkhad confirmed its use of GPS data in recommendingpotential friends spread quickly across the web on Monday, thrusting Facebook into the centre of a heated digital privacy debate (yetagain.)

The criticism becameso heated, apparently, that it promptedFacebookto contact Hill on Monday nightafter it had "dug into the matter" further to say that location data was not, in fact, used to suggest people users may know.

After all, as Fusion notes, sharing theidentitiesofusers witheachotherbefore gettingaffirmativeconsent may be aviolation ofFacebook'sagreement with theFederal Trade Commission.

In a statement sent to CBC News on Tuesday, a Facebook spokesperson similarlydenied the initial reports.

"We're not using location data, such as device location and location information you add to your profile, to suggest people you may know," the spokesperson said. "We may show you people based on mutual friends, work and education information, networks you are part of, contacts you've imported and other factors."

Facebook's fast flip-flop on this has some critics curious about why and what's actually true.

It's already knownthat Facebookuses smartphonelocation data for advertising purposes, and that it "tested" using location data for friend suggestions last year.

We show you people based on mutual friends, work and education information, networks you're part of, contacts you've imported and many other factors.- FacebookHelp

There are also many accounts of users being freaked out byFacebook'seerily accurate friend suggestions to be found posted online fromboth before andafterFusion's story was published.

"Last year I was dropping my daughter off at a friend's house. The friend's dad met me at the door and we chatted. It was the first time that we had ever talked about anything. Literally just met the guy," wrote a commenter on Slashdotin response to Monday's reports. "In our conversation, we mentioned an app that he just started using (and was in fact using when I pulled up).It's an app that I would never use since it was about golf and I don't play or care about golf."

"Before I pulled out of his driveway I checked Facebook," he continued."I kid you not, an ad for that app was on my news feed. I'd never seen it before, ever. Somehow they correlated his installation of the app, with my account, and showed me something that there was a chance we discussed."

Here's how to change or turn offlocation services on a smartphone, ifyou're interested.