Mac clone maker Psystar owes Apple Inc. $75,000, according to recently filed documents in the Florida company's federal bankruptcy case.

On Thursday, Apple spokeswoman Susan Lundgren declined to comment about what the debt represented, but said she would look into the matter.

Under "Schedule F -- Creditors Holding Unsecured Nonpriority Claims," Psystar listed Apple Inc. and said it owed the California computer maker $75,000. The only other information on the form was the phrase "Litigation Pending" in the section where Psystar was to provide "consideration for claim."

The contact name listed for Apple in the document was Paul Singerman, a Miami attorney and the co-CEO of Berger Singermman, a law firm that specializes in bankruptcy proceedings. Singerman's office confirmed that he was representing Apple in the Psystar bankruptcy case.

It's unclear what comprises the $75,000 Psystar owes Apple. Last January, the Mac clone maker, which is being sued by Apple because it installs Mac OS X on generic Intel-powered computers, said it bought copies of the operating system from Apple itself.

"Psystar distributes computers with legitimately purchased copies of Mac OS loaded thereon," the company said in the January 2009 filing. "Many of those copies [were] directly obtained from Apple."

It's possible that all or part of the $75,000 represents Mac OS X orders Psystar placed with Apple. At the list retail price of $129 per license, the $75,000 translates into 581 copies of Leopard.

Psystar filed for Chapter 11 protection protection 21 May and claims over $334,000 in debts to several creditors other than Apple, including its own law firm, Carr & Ferrell, and several shipping companies and component suppliers.

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