At least unless you say otherwise. The social network has admitted that more than 800,000 were hit by a bug that meant people they had blocked on either Facebook or Facebook Messenger were temporarily unblocked and able to see content that had been posted.
While the issue has now been fixed - all unblocked users are blocked once again - the bug was active for 8 days, impacting users between May 29 and June 5. It would, however, allow a blocked user to do things like contact you on Messenger, or try to re-add you as a friend.
Mind you, they couldn't see private posts, or posts you'd only shared with your friends.
"We know that the ability to block someone is important, and we'd like to apologise", Egan said.
Blocking someone also automatically "unfriends" the person. "People who were affected will get a notification on Facebook encouraging them to check their blocked list", Egan added.
Responding to Facebook's blog, TechCrunch's Josh Constine said in a tweet that the block bug would further shake the confidence of stalking and abuse victims who trust the platform.
Apparently, the bug did not cause unblocked users to become friend with the users who had blocked them even if they were friends before getting blocked.
In its original statement, Facebook pointed out why someone might want to block another user.
When Mashable reached out for more information on the bug, a Facebook representative informed us that the bug was random and global, affecting users from all over.