In the letter, Apple states that Psystar has failed to produce "customer purchase receipts or order documents" from April 2008 (when Psystar began selling their computers with Mac OS X preinstalled) until October 2008. Documents from after that period have been handed over. According to Apple, "Psystar has produced no monthly profit and loss statements, balance sheets or other financial statements and only a small subset of revenue and cost-related receipts."
Apple has stated in the past that it believes Psystar is not acting alone, and that third parties are financing the clone maker's efforts. Apple picks up this mantra in the letter. "Moreover, at the deposition regarding Psystar's revenues, profits, assets and liabilities (including investors, lenders or other sources of financial support), taken on March 20, 2009, Psystar's CEO and founder Rudy Pedraza, the person designated by Psystar to testify on this topic, would not answer basic questions about Psystar's financials."
It seems like Apple still believes there's more to all this than just Psystar, and that other people or companies might be financing Psystar, which would then, I assume, explain why Pedraza couldn't answer questions about "investors, lenders or other sources of financial support". Of course, a much more plausible explanation would be that there are no "investors, lenders or other sources of financial support", but that's far less exciting.
Apple websites are of course accepting this letter as a statement of fact, while it's obviously just one slanted side of the story. Psystar has so far not responded to Apple's accusations, and since at least I live in a world where guilt has to be proven, I'll reserve judgement until we know a little more about this.
In the meantime, the case itself will of course continue. In case you've been living under a rock the past 12 months, Psystar started selling computers with Mac OS X pre-installed last year. The EULA for Mac OS X has a clause which forbids installing Mac OS X on anything but an "Apple-labelled computer", and this specific clause is at the centre of the legal battle between Apple and Psystar.
Psystar believes it should be able to pre-install legally purchased and fully paid-for copies of Mac OS X on machines it then sells to customers, while Apple believes the computers in question need to be "Apple-labelled", but what exactly "Apple-labelled" means has never been made clear by the Cupertino company.
The case is also about things greater than just Apple vs. Psystar: are software companies allowed to place post-sale restrictions? Is an EULA a binding contract just because you click "Ok"? Should EULAs be presented before purchase? Should software companies be allowed to remove rights granted to consumers by copyright law?