Soundgarden, Tom Petty’s ex-wife Jane, Hole, Steve Earle and the estate of Tupac Shakur have filed a lawsuit on behalf of a class against Universal Music Group, seeking damages related to a 2008 fire that allegedly destroyed over 500,000 recordings.

The suit accuses Universal Music of negligence in not doing enough to prevent the fire, as well as concealing the extent of the destruction from artists while simultaneously pursuing litigation and insurance claims to recoup losses. The suit claims that Universal took in settlement proceeds and insurance claims valued at $150 million, and the class is seeking damages worth half that, plus half of any additional losses.

While the fire was widely covered in 2008, the extent of the damages was not well known until a recent New York Times Magazine report. The story alleged that among the half-a-million recordings destroyed were irreplaceable master tapes and troves of unreleased material from artists such as Louis Armstrong, Ella Fitzgerald, Etta James, Chuck Berry, Elton John, Nirvana, the Roots and Janet Jackson (all artists named in the Times story are listed as potential members of the lawsuit’s class).

Much of the lawsuit is focused on the alleged loss of those master recordings, and the suit argues that all potential members of the class “have an expectation that under their recording agreements with UMG there will be a 50/50 sharing of revenues derived from” the use and release of their work. It also claims that UMG violated good faith and fair dealing in all those contracts by allegedly failing to “take reasonable measures to preserve and maintain” those recordings.

Howard King, one of the attorneys leading the lawsuit, tells Rolling Stone, “Our lawsuit on behalf of all affected artists describes a devastating loss of precious master recordings, concealed from the artists for more than a decade. We seek an accounting of every lost master, including outtakes and preciously-unreleased material, as well as a fair share of the tens of millions of dollars received by Universal as compensation for the loss.”

A representative for Universal Music declined to comment.

The lawsuit uses UMG’s own words against it, pulling extensively from legal documents filed in the aftermath of the fire against its parent company Vivendi, plus NBC and Universal City Studios, which owned the warehouse on the Universal Studios lot where the UMG vault was located. The quoted portions suggest that proper preventative measures, such as updating a sprinkler system, were not taken, even after a different fire broke out in 1990. The new class action lawsuit claims that UMG, being a part of the Universal Studios family, was as aware of these issues as much as Vivendi, NBC and Universal Studios.

The suit also argues UMG embarked on a “systemic and fraudulent scheme of misrepresentation and misdirection” after the fire. It includes quotes that UMG gave to media outlets after the fire downplaying the damage, such as “We only lost a small number of tapes and other material by obscure artists from the 1940s and Fifties.”

While UMG continued to dispute the extent of the damage even after the Times report, the label has reportedly also vowed to be as transparent as possible with artists seeking information about potential losses. UMG CEO Lucian Grainge sent a memo to employees earlier this week, saying, “We owe our artists transparency. We owe them answers. I will ensure that the senior management of this company, starting with me, owns this.”

At the moment, it still remains unclear what master tapes and recordings were actually lost in the fire. The specific artists leading the new class action suit did not name any particular or notable recordings of theirs that might’ve been destroyed.