In early January, Facebook updated their iPhone app to include a Contact Sync feature. In a nutshell, “Facebook Contact Sync” allows you to synchronise your friends’ latest Facebook profile pictures with the matching contact entry in your mobile phone’s address book. Due to “Terms of Service Issues” however, Facebook does not sync your friends email addresses or phone numbers (listed on their Facebook profile) TO your phone.

Ironically, what Facebook WILL DO, with neither your knowledge or consent, is import ALL the names and phone numbers FROM your phone’s address book and upload them to your Facebook Phonebook app (Click HERE to see your Facebook Phonebook) on Facebook.com, thus storing your private contact numbers on Facebook‘s servers. Once your phone is synced , Facebook will attempt to match the newly uploaded phone numbers to users that have listed the same phone number on their Facebook profile, wether you are friends with them or not. If Facebook cannot make a match, it will create a new contact entry in your Facebook Phonebook using the contact details imported from your phone, and add a link to invite them to join Facebook. And guess what? There is no way to delete the names and numbers Facebook imports from your phone’s address book.

Boom. You just got jacked by Facebook.

So what is so worrisome about Facebook uploading your mobile phone’s address book to their servers? Several things:

1) Facebook doesn’t warn users that they are uploading their phone’s adress book to Facebook. In fact, because Facebook doesn’t sync contact numbers or email addresses TO your phone, most users wrongly assume that Facebook Contact Sync only syncs user pictures. In reality though, they are pumping your address book, without your consent.

2) Phone numbers are private and valuable. Most people who have entrusted you with their phone numbers assume you will keep them private and safe. If you were to ask your friends, family or co-workers if they are ok with you uploading their private phone numbers to be cross-referenced with other Facebook users, how many of them do you think would be ok with it?

3) Facebook doesn’t exactly have a perfect track record when it comes to protecting your privacy. And whilst it’s unlikely that your data will fall into the wrong hands or be used for evil, it’s still a possibility. If you can look past that and entrust Facebook with your own information, that’s fine. But can you really make that call (pun painfully intended) for every single person in your mobile phone’s address book? Would you like it if someone else was making that call about your own private information?

4) Facebook‘s privacy policy isn’t a two way street. While they won’t let you sync phone numbers and email addresses from Facebook TO you mobile phone, they are quite happy to to sync ALL your phone numbers on your mobile phone TO Facebook and not let you delete it. How is that not a Terms of Service issue?

5) Whilst checking my Facebook Phonebook, I noticed that there were a number of people that I did not know and was not friends with. Facebook had matched them to phone numbers imported from my phone. Turns out some of these unknown users had fraudulently listed the phone numbers of hotels or businesses, that I had saved on my phone, as their own. Other users simply had phone numbers that matched some of my contacts due to both them and I not including an international dialling code before the phone number in question.

Here is another scenario: Random guy, meets random girl in random club. Girl gives boy phone number. Boy is blasted. Boy doesn’t enter phone number correctly and confuses the last two digits. In a twist of fate, the phone number he enters is YOUR phone number (Your phone number and random girl’s phone number are the same, except for the last two digits). Boy syncs phone to Facebook. Facebook matches your newly uploaded phone number to your Facebook profile. Now random boy has your name, Facebook profile and phone number. Unlikely scenario, perhaps, but still possible. When a wrong number is dialed, someone usually picks up, right? Well why couldn’t that person be you?  The point is your phone number is being cross referenced in a system-wide Facebook phone directory, and you never opted in.

6) Facebook is notoriously littered with hundreds of malicious “Facebook Apps“, phishing scams and hacked accounts. Their sole purpose is to pump your account for your private data and that of your connected friends. Facebook is not the type of environment most users are comfortable storing phone numbers on, nor should it be. As much as I have defended Facebook in the past, the amount of hacked accounts I see on a regular basis on Facebook forces me to think otherwise.

The Bottom Line:

I’m not suggesting uploading your address book online is tabboo. A large portion of my address book lives in Gmail, so I’m no stranger to the concept. In fact, I’m a fan. The difference is, with Gmail I did so willingly. It wasn’t done so for me or without my consent. Furthermore,  I chose WHICH contacts I wanted to backup online. There are some contacts and phone numbers who’s privacy I simply refuse to risk on the Web. Facebook has taken and continues to take liberties on behalf of their users. Their perception of privacy and their users perception of privacy is often very different. I don’t think this is maliciousness on Facebook‘s part, but it does show me that Facebook is painfully out of touch with the needs and beliefs of their CORE users, who are still wary of the openness that a Web 2.0 lifestyle entails. It’s their right. Facebook needs to either respect that or openly provide a disclaimer that they do not.

(NOTE: The above post outlines my experience with Facebook Contact Sync and my iPhone. If you are a Blackberry, Palm Pre, Android or other platform user, please leave me a comment bellow outlining your own experience and/or feeling on this subject matter. Much Thanks!)

  • ppsignup

    To be honest, I'll still sync my facebook with my contact list. However it is true that this truly does violate mine and others privacy and it's just another point in the long line of facebook privacy fails.

  • ppsignup

    To be honest, I'll still sync my facebook with my contact list. However it is true that this truly does violate mine and others privacy and it's just another point in the long line of facebook privacy fails.

  • SO

    Have you find a way to erase the phonebook on Facebook?

  • SO

    Have you find a way to erase the phonebook on Facebook?

  • inTOWN

    I just figured out the same… Accidentally I found the Facebook Phonebook, to figure out it had synced all my iPhone contacts. I am no internet/computer stranger, (in fact it's my work). I'm 100% sure I never agreed to sync my iPhone contacts to Facebook or any other internet server/application. I did however agree to sync (photos) of my Facebook contects TO my iPhone. Yet, all my phone numbers were to be found in Facebook. Hidden away and not to be edited or deleted.
    I was a big (promoting) Facebook fan, but this made me not sleep last night. I feel so fooled!
    When you upload photos or private info to Facebook > you do so willingly… but taking your info without you knowing is STEALING! It feels that it has been done on purpose and don't understand why so little people know about this problem..

  • http://www.facebook.com/people/Kurt-Von-Moos/502792923 Kurt Von Moos

    Unfortunately… No. Looks like our contact information now belongs to Facebook…

  • http://www.facebook.com/people/Kurt-Von-Moos/502792923 Kurt Von Moos

    I feel your pain. When I first discovered this, I did a quick Google Search for the issue, and much to my surprise, I could not find a single blog post on the subject. Hence, my blog post above.

    Put it this way, I find it harder and harder to defend Facebook nowadays…

  • SO

    Please join this group: http://www.facebook.com/group.php?gid=103226533
    And feel free to create one in english.

  • SO

    Please join this group: http://www.facebook.com/group.php?gid=103226533
    And feel free to create one in english.

  • bil swan

    Dam-it, I just did the same dam thing.

  • bil swan

    Dam-it, I just did the same dam thing.

  • kurtvonmoos

    I've left a comment on your Facebook group.

    Thank you so much for spreading the word. It's much appreciated :-)

  • kurtvonmoos

    I've left a comment on your Facebook group.

    Thank you so much for spreading the word. It's much appreciated :-)

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  • Brunetbeauty88

    can you delete numbers from the phone book once added

  • Socacofl

    Unfortunatelty no

  • http://daveoshana.com/ Dave Oshana

    Could Facebook be testing how much people are like lemmings?
    http://society.oshana.org/leave-facebook-find-f

  • scape

    the problem i have with it is that my number is on “sally's” phone, and it gets synced to facebook, i can't stop that and now my number is on their server. bullshit

  • http://backgroundfinder.com/ people finder

    The best way to protect your privacy on Facebook does not share any information related credit or private that you do not want your worst enemy to know. So to protect your credit and your identity is used by others are on Facebook right now and edit your profile in areas that affect your privacy.

  • Teepo_15

    Agreeance with most of the article, except the terrible final paragraph. It seems kurt is painfully out of touch with Facebook Core users. Though this is mildly interesting, 98% of facebook users don’t care if a phone sync’s up contacts, nor most things to do with privacy protection. Maybe by CORE you mean, lawyers, policemen and governments. I don’t care that a syncing device does this, nor will 98 out of a hundred people you talk to.
    As for some privacy disclaimer how about this for the 2 % of people who seem to be out of touch with the rest of facebook’s CORE users….. You’re on FACEBOOK. It’s about connecting, sharing, and openness. There’s always going to be a lack of privacy.

    Don’t like it? Leave.

    Simple. But of course, we all know you will not.

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  • http://www.facebook.com/sam.bailey Sam Bailey

    You can delete them. The link is on the right-hand-side of the Phonebook page.

    http://www.facebook.com/contact_importer/remove_uploads.php?r=%2Fphonebook

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    The best way to protect your privacy on Facebook does not share any information related credit or private that you do not want your worst enemy to know. .That’s what i also believe.

  • http://www.moldremoval.net Mold removal contractor

    great article.Good to know about it. thanks.

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    Thanks for giving me a break from work! Keep some good things to read.i Agree with most of the article.

  • http://www.k9stud.com Puppies For Sale

    Me also noticed this few days ago. Some of my female friends has informed me about this and they really feel unsafe of this. I request Facebook team to take quick action.

  • http://www.hobbybreeders.com Dog Breeders

    98% of facebook users don’t care if a phone sync’s up contacts, nor most things to do with privacy protection. Maybe by CORE you mean, lawyers, policemen and governments. I don’t care that a syncing device does this, nor will 98 out of a hundred people you talk to.

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    good site.

  • http://www.corporateintranet.org Corporate Intranet

    Facebook does not share any information related credit or private that you do not want your worst enemy to know. .That’s what i also believe.

  • Private

    thank you for your information.

  • Lindsayshaunda

    I woke up last week and went to edit a friend and saw a phonebook app. opened it up and all my friends phone numbers were made public by face book . I am a real estae agent with all my clients private numbers in my phone and e-mail. So far my clients numbers havent been added to it yet but this worries me. I did not use the contact sync and truthfully wasn’t aware of an phonebook app. I dont share my contacts with anyone. I dont upload photos or anything from my phone to facebook. Now I cant delete my friends unlisted numbers..I called verizon and actually had to put an internet block on my and my families phone so it cannot steal from my phone again. This is freaky

  • http://www.healthcompedium.com hecatom

    At least, third parties can’t do that. Mostly.

  • Mohammed Sadique

    Facebook does not actually provide a mechanism for users to close their accounts, and thus raised the concern that private user data would remain indefinitely on Facebook’s servers.However, Facebook now gives users the options to deactivate or delete their accounts, according to the Facebook Privacy Policy. “When you deactivate an account, no user will be able to see it, but it will not be deleted. We save your profile information (connections, photos, etc.) in case you later decide to reactivate your account.” The policy further states: “When you delete an account, it is permanently deleted from Facebook.A third party site,USocial, was involved in controversy surrounding the sale of fans and friends, but it received a cease-and-desist letter from Facebook.Facebook had allowed users to deactivate their accounts but not actually remove account content from its servers. A Facebook representative explained to a student from the University of British Columbia that users had to clear their own accounts by manually deleting all of the content including wall posts, friends, and groups.Facebook subsequently began allowing users to permanently delete their accounts. Facebook’s Privacy Policy now states: “When you delete an account, it is permanently deleted from Facebook.Its better for all of us to leave facebook and join another social networking site like http://incliq.com/ , because it protect our privacy with its technology.

  • Aoe

    they can’t sell that info, they don’t even share it without your consent. OH NO A PHONE NUMBER IS SITTING ON A SERVER DOING NOTHING!

  • Aoe

    if you added them from your phone, yes. If your friends said, FACEBOOK, this is my number and let brunetbeauty88 see it, then no.

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    Privacy Fail: How Facebook Steals Your Friends Phone Numbers

  • http://moneyproa1.blogspot.com earn money online

    People should care about any application before they open it. If you accidentally or interestedly accept any application just remove them from privacy settings. Thanks.

  • eq

    Linking every single instance of the word “Facebook” to the site is unhelpful and visually distracting. Is this a trick to bolster your search rankings?

  • cirovladimir

    I didn’t noticed until I read your comment….

  • http://www.hawaiiwego.com/ Hawaii Condos

    Facebook has now more effective privacy policy. This problem has been solved already. It can now protect your privacy better than before.