The Real Reason Why You can't block Mark Zuckerberg or Priscilla Chan

Bad news! You still can’t block Mark Zuckerberg on Facebook. And now you can’t block his wife Priscilla Chan either.
The saga began back in January, when people first noticed that Zuckerberg’s account was immune to the block button.

You can hit “block” on the Facebook chief executive, and the site asks you to confirm your intentions (you can almost see the puppy dog eyes) – but if you do confirm, a warning comes up noting something along the lines of “this profile can’t be blocked for now”.

With Zuckerberg, it was a particularly noticeable problem, since his posts are seemingly given extra viral oomph by Facebook’s newsfeed algorithm, leaving him ever present in the feeds of many.

But the problem has now spread to another member of the Zuckerberg family. Chan is also unblockable. The family dog, Beast, also has a Facebook page, but he can be blocked, if you are a monster. Oh, and his sister Randi.
The quirk isn’t deliberate, according to Facebook. A spokesperson in July said: “This error isn’t specific to any one account. It’s generated when a person has been blocked a certain large number of times. In very rare instances, a viral campaign will develop instructing lots of people to all wrongly block the same person.”
A former Facebook engineer further clarified that the error is a side-effect of the way blocks are coded in the site, rather than a specific decision to prevent too many people blocking the same person.