Last week, one of the most popular songs of all time, “Happy Birthday” was considered public domain, allowing it to be used at any time without having to pay for the copyright. Now TV shows, movies, radio shows and any public forum can play it and sing the song whenever they want.

You’re probably thinking that this was already allowed, in which case you would be wrong. Happy Birthday is based on the song which has credited American siblings Patty Hill and Mildred J. Hill as composers in 1893. Warner/Chappell Music purchased the rights to the song in 1935, where at that time, the copyright was set to expire in 2030 and that unauthorized performances of the song would cost up to $700 at one point. By one estimate, the song is the highest earning single song in history, with estimated earnings since its creation of  $50 million.

So what does all of this mean? Well, it doesn’t mean that you should pay $700 every time your family sings this classic song on your birthday. Copyright law dictates that a song under copyright cannot be used to earn money for another company. So since you singing in your house isn’t using the song to earn you money, you can wipe the sweat off your forehead because the FBI won’t be knocking down your door today.

This month, a federal judge ruled that the copyright held by Warner/Chappell Music is not actually valid, declaring that it only applies to a specific piano arrangement of the song.

After this ruling, it was decided that the song itself, is now public domain. Public Domain is a category of music that is copyright free, and therefore can be used by anyone. Some examples of PD songs are “For He’s a Jolly Good Fellow,” “Home Sweet Home,” “Yankee Doodle,” and “Row Your Boat.”

Now with Happy Birthday added to that lists, many public shows and performances took advantage of this new freedom and decided to sing this song loud and proud over the past week. Also, if you end up on TV in the near future, feel free to sing happy birthday to someone just for fun.