Agreeing with -TruBlue, you are allowed to share the month and day of your birthday, just not the year because that would reveal your age. Another note worthy thing on a slightly unrelated note is you are allowed to share your first name, that is because, similar to not being allowed to share the year you were born, people can find out who you are by your last name, but if it just your first name, (e.g. Sam) there are millions of people with the name "Sam" on earth so it is impossible to find out which Sam (or whatever your first name is) plays Chicken Smoothie.