Facebook basically sends only one notification per birthday to users. It also sends emails only to those users who have opted either actively or passively to receive them. However, over the last one month, few users have reported a huge increase in notifications from the website, sending multiple pokes over various media to wish happy birthday to friends. While many suppose that the change was intentional, or probably a form of user experience testing, as with so many of the site’s undocumented changes, it was seemingly an unusual accident. The bug, which has now been amended, resulted in users who had never signed up to email notifications for birthdays still incorrectly being sent the missives confirmed Slate’s Jacob Brogan to Facebook. “It was not immediately clear whether the other, similarly persistent, notifications were part of the same problem”, Brogan wrote. So, from now on you will be getting only one bump from now on irrespective of whether you have signed up on purpose or by accident.