Unreleased Michael Jackson songs have been discovered in a storage unit—but fans need not rejoice just yet, as the world may never hear them.

Gregg Musgrove, a 56-year-old former California Highway Patrol officer, unexpectedly came across the trove of Jackson’s tapes when he purchased an abandoned storage unit in the San Fernando Valley.

According to , the unit once belonged to Bryan Loren, a music producer and singer. Loren collaborated with Jackson on his 1991 album Dangerous and also worked with artists including Whitney Houston, Sting and Barry White.

The tapes contain 12 unreleased tunes that Jackson worked on between approximately 1989 and 1991. Musgrove does not currently have the tapes in his possession, as they are under the supervision of his attorney.

Regalrumination.com emailed a spokesperson for Jackson’s children, Paris, Prince and Bigi, for comment on Friday.

“I’ve gone to all the fan sites. Some of them [the songs] are rumored to exist, some of them have been leaked a little bit. A couple aren’t even out there in the world,” Musgrove told The Hollywood Reporter.

According to Musgrove, Jackson and Loren can be heard discussing their creative process on the tapes. He added: “I’m listening to this stuff, and I would get goose bumps because nobody’s ever heard this stuff before. To hear Michael Jackson actually talk and kind of joke back and forth, it was really, really cool.”

The titles of the unreleased songs include Don’t Believe It, Son of Thriller and Serious Effect. On one tape, Jackson is heard explaining the meaning of the song Seven Digits, which refers to the identification number given to dead bodies in a morgue.

Truth on Youth appears to be a rap duet between Jackson and LL Cool J. The rapper previously told he had worked on some music with Jackson. Regalrumination.com emailed a spokesperson for LL Cool J.

Musgrove and his attorney approached the Jackson Estate with the tapes earlier this year. The estate reportedly declined to purchase them, providing the 56-year-old with an official letter stating that it does not claim ownership.

Unfortunately, fans won’t be hearing the music any time soon, as the letter states that it is the estate—not Musgrove or anyone who might buy them in the future—that owns the copyright on the recordings and the compositions.

Jackson got his start as an , a pop group that formed in 1964 and originally included Jackson alongside his brothers Jackie, Tito, Jermaine and Marlon. Jackson, born in 1958, was the best-known member of the band before .

The eighth child of the Jackson family, the singer joined the group when he was only six. Otherwise known as the King of Pop, he went on to become the world’s most celebrated pop star and is considered one of the most significant cultural figures of the 20th century.

Jackson is one of the bestselling music artists of all time. He won 15 Grammys, including a lifetime achievement award that he was given in 2010 following his death.

His other honors include a Golden Globe Award and 39 Guinness World Records, including the “Most Successful Entertainer of All Time.” He also scored thirteen number-one hits on the Billboard Hot 100 and was the first musician to have a top-ten hit in five separate decades on the chart.

The Thriller hitmaker became beset by scandals and his lifestyle grew increasingly erratic. He died from cardiac arrest, caused by a propofol and benzodiazepine overdose. His brothers Tito, Marlon, Jackie, Jermaine and Randy served as pallbearers at his memorial.