Facebook recently came under a lot of fire for storing contacts and phone numbers from your phone contacts directly on their servers. This feature was part of the mobile sync they have in their apps. This feature formerly known as Phonebook has been available for a long time, however some recent Facebook mass updates caused it to come to the fore.
Facebook has said that the Phone Numbers "Published" to Everyone is Fake, however, they still have the data they have synched from the phone with them.
If you are not comfortable having your business or personal contacts phone numbers, emails and other information stored on Facebook, here is how you can delete them.
Step 1: Head over to Facebook.com on a desktop PC and log in. Once you have done that, click on the "Account" menu in the right hand side corner and then click on the "Edit Friends" link.
Step 2: On the Edit Friends page, click on the "Contacts" option in the left hand side sidebar of the page.
Step 3: If you have used Facebook on your mobile device, you will see a list of all the contacts here. To delete these contacts from Facebook, click on the link that says "this page" or visit this link directly (requires login).
Step 4: On the next page, Facebook will give you the usual yada yada about why you should not delete your Facebook contacts and how it will help you. If you are very sure about deleting the message you should just ignore it and click on the "Remove" button.