Unless you’ve been in a bunker with no outside contact, I’m sure you’ve heard that Led Zeppelin have had to defend the intro to “Stairway to Heaven” in court for a while. The case may be going to the top and heading to the Supreme Court.

The estate of Michael “California” Wolfe and their representative, Michael Skidmore, are petitioning the highest court to secure an appeals case.

Wolfe was the lead singer and songwriter for the band Spirit. Since 2014, the estate and it’s representatives have tried numerous times, and failed each time, to mount a legal argument that “Stairway To Heaven” breached copyrights because of the alleged similarities to the Spirit song “Taurus.”

Wolfe wrote “Taurus” before federal law protected sound recordings, which has been the issue that has complicated previous appeals. Under earlier laws, dating back to 1909, songs were protected through deposits of original sheet music with the U.S. Copyright office. The judge in the original case said that jurors would not hear recordings of either song.

Skidmore says that making a decision based on sheet music denies older songwriters of their intellectual property.

This isn’t the first time Zeppelin have been accused of stealing music. They have been accused of ripping off Joan Baez, Jake Holmes, Muddy Waters, and Moby Grape.

Have a listen to both songs and decide for yourself.