Mike Lynch is suing HP for at least $150m in damages.
The suit comes as a result of the claims that he helped to cook the books in order to inflate the price that was paid for Autonomy.
Autonomy founder and ex-CEO Lynch, has consistently said that HP’s claims are false.
Lynch, regarding his suit, said: "Over the past three years, HP has made many statements that were highly damaging to me and misleading to the stock market. Worse, HP knows, or should have known, these statements were false."
Lawsuits filed against Lynch by HP have been made in both the UK and US, however, in January the Serious Fraud Office said that there was insufficient evidence for a realistic conviction, so the probe was ended. Proceedings are on-going in the US.
An HP spokeswoman, said: "Mike Lynch’s lawsuit is a laughable and desperate attempt to divert attention from the $5 billion lawsuit HP has filed and the ongoing criminal investigation. HP anxiously looks forward to the day Lynch and Hussain will be forced to answer for their actions in court."
The on-going dispute stems from the 2011 acquisition by HP of Autonomy for $10.7bn, a year later HP accused Lynch of misrepresenting the value of his organisation.
This led to the company writing down its value by $8.8bn and commenced legal proceedings.
