The founder of Autonomy, Mike Lynch, has filed a lawsuit against HP in the UK courts seeking more than $150m in damages.
The move is the latest in the battle between HP and Lynch, after HP accused the ex-Autonomy CEO of inflating the company's financials to gain a higher sale price.
Lynch said he has taken the action due to reputation damage.
"Over the past three years, HP has made many statements that were highly damaging to me and misleading to the stock market. Worse - HP knew, or should have known, these statements were false," he explained.
"We are finally starting to see what really happened with Autonomy. HP's own documents, which the court will see, make clear that HP was simply incompetent in its operation of Autonomy, and the acquisition was doomed from the very beginning."
Lynch went on to lay the blame for failure firmly at HP's door, claiming the firm was in chaos at the time and tried to abort the Autonomy deal after closing.
"HP wasn't misled by us or anyone else - evidence will show they didn't even read their own due diligence report," he added.
Back in May, HP released a number of documents relating to its case and claims against the founders of Autonomy, accusing Lynch (pictured below) and former finance officer Sushovan Hussain of fraud.
A statement from HP at the time said that Lynch and Hussein pushed Autonomy, which HP purchased, into bad accounting practices, and inflated its worth and net profits.
The company has attempted to get some of that investment back, and has been engaged in a legal war of words ever since.
The documents released in May made for interesting reading, pulling in items like Tottenham Hotspur football club and a $10m van.
"This conduct by Lynch and Hussain was systematic and was sustained for more
than two years prior to the acquisition of Autonomy by HP," the firm said.
"Its purpose was to
ensure that the Autonomy group's financial performance, as reported in Autonomy's published information, appeared to be that of a rapidly growing, pure software company whose performance was consistently in line with market expectations.
"The reality was that the group was experiencing little or no growth, it was losing market share, and its true financial performance consistently fell far short of market expectations."
Autonomy's founders said in a detailed blog post, supported with evidence and copies of legal communications, that HP purposefully blurred the case and smeared Autonomy's business.
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