Mixed Blood Theatre has filed a nearly $350,000 claim on Prince's estate, submitted days before the Sept. 12 deadline for those seeking a piece of the late musician's multimillion dollar fortune.

The Minneapolis theater is trying to recoup expenses related to its 40th anniversary gala, which was planned for May 14 at Prince's Paisley Park complex and canceled just over a week in advance by Bremer Trust, the special administrator overseeing the estate.

"This was the biggest thing we'd ever planned, and a great number of people had spent a year planning it," said the theater's artistic director, Jack Reuler.

Prince died April 21 of an accidental overdose of fentanyl, but Paisley staffers assured Mixed Blood that the event would go on. Then, after theater staff were notified of the cancellation, Reuler said, attorneys for Bremer and the trust's president "assured us that we would be made whole," he said. The filing of a formal claim is an effort to ensure that ongoing negotiations to recover costs associated with the gala will be recognized by the courts.

"Ever since May, we've been dealing with Bremer Trust. We went to mediation with a judge," Reuler said. "We didn't come to a number that both sides agreed to, so the process continues … and we will come to a natural conclusion."

Mixed Blood said its claim for $348,358 was based on galas and fund­raisers undertaken by similar organizations, items that had been collected for silent and live auctions, tickets and sponsorships that had to be refunded, games, a photo booth and other items.

The theater has laid off staff since the gala was canceled, though the number of people is unclear.

"There was more staff May 5 when we canceled the event than we had on Aug. 5," Reuler said.

Mixed Blood's claim is among dozens filed against the estate by purported heirs and creditors since Prince's death. His estate has been valued between $100 million and $300 million before taxes.

Mixed Blood's claim was filed Sept. 7 but did not appear in the public record until Monday.

Public release of court filings in the case has periodically been delayed. And several documents have been filed under seal, including orders explaining why those documents were kept from public view.

Recent court filings suggest that Carver County District Court Judge Kevin Eide, who has presided over the case since shortly after Prince's death, has occasionally kept documents from appearing on the public docket. Two orders were filed Monday, and sworn statements from attorneys for Bremer Trust and consultants it hired to help maximize the value of Prince's estate.

The issue came to light Aug. 29 when Eide unsealed an order related to the conversion of Paisley Park into a museum for public tours. The judge's order referenced affidavits filed by Bremer Trust and consultants working for them, but he left those affidavits sealed and no docket entry reflects that they were ever filed.

Following an inquiry from the Star Tribune, courts spokesman Kyle Christopherson said Eide is considering whether to unseal the affidavits.

Christopherson said Eide and the court staff are moving as quickly as they can.

"This isn't their only case," Christopherson said. "Sometimes the judge needs to weigh in on access to the document. They're not going to release it until they're absolutely certain that it's publicly accessible."

Courts tend to allow this kind of secrecy in family law, probate and similar kinds of cases, said University of Minnesota law Prof. Jane Kirtley. But the public interest in those cases can get lost amid privacy concerns.

"Our courts are supposed to be open. They're not supposed to be secret," Kirtley said. "And this notion that because it's dealing with finances or family matters or whatever, that the public has no interest in it — we do have an interest in knowing how our courts operate."

Staff writer Jon Bream contributed to this report.

Emma Nelson • 612-673-4509