Warner/Chappell Music has long owned the rights to "Happy Birthday to You," and any TV or movie producers who want to use the song must pay up to do so.

But filmmakers behind a documentary about the popular song are locked in a legal battle in California with Warner/Chappell. On the night before a decision in the case was supposed to come down, lawyers for the plaintiffs discovered evidence that could change the tides.

Eriq Gardner, senior editor at The Hollywood Reporter, joined the show to explain more.

To listen to the full interview, click on the blue audio player above.