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Hewlett-Packard acquired Autonomy in 2011 for over $11 billion. A year later, it announced the $8.8 billion write-down, saying $5.5 billion of it was because of "serious accounting improprieties, misrepresentation and disclosure failures" by Autonomy.
The document, which Lynch said he only recently obtained from a source within HP, details the deals taken out by HP in order to produce the numbers and the write-down, he claimed. What it comes down to, he said, is differences in accounting practices in the U.S. and U.K.
"Nowhere in this rebasing document does it talk about fraud," Lynch said. "What it also shows is that there was no money missing."
Hewlett-Packard denied Lynch's claims. "The same fertile imagination that was behind a massive fraud is apparently still hard at work making up stories. We would encourage Mr. Lynch to spend as much time as possible with the authorities," it said in a statement to the Financial Times.
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Lynch said one of the problems with the deal was that HP put an "astronomical amount of projected synergies into the deal."
"When it mismanaged the business and it could no longer deliver on those, that is what led inevitably to the write-down," he said. "But rather than actually give the real reason for the write-down, what they have done is give this concept that somehow it was a fraud."
—Reuters contributed to this article.