Slaughter and May senior partner Steve Cooke has been called on as a witness in one of the U.K.'s largest civil fraud cases – the $5 billion damages claim by U.S. technology giant Hewlett-Packard against two former Autonomy software directors.

According to the 900-page written opening statement lodged by the claimants' counsel in London's High Court on March 8, Cooke has provided a written witness statement that could see him called to the stand later in the year. Witnesses are due to start being called from today (April 1) in the High Court.

Hewlett-Packard and three other claimants are suing former Autonomy chief executive Dr Mike Lynch and ex-chief financial officer Sushovan Hussain, alleging the two engaged in a "deliberate fraud perpetrated by the defendants" as part of the £7.1 billion purchase of Autonomy by Hewlett-Packard in 2011.

Cooke and former corporate partner Gary Eaborn headed the Slaughters' team, which took the lead role advising Autonomy on the deal.

According to the opening statement, Cooke's evidence "exclusively addresses when Slaughter and May was first approached by Dr Lynch about putting Autonomy up for sale".

A spokesman for Slaughters declined to comment on the content of the statement or on the case.

Travers Smith is representing all four claimants in the UK case, with disputes partners Toby Robinson, Andrew King, Jan-Jaap Baer and Stephanie Lee leading for the firm.

In the written opening statement, Cooke is first referenced as being among a "rollcall of witnesses", for Lynch, counting, "such eminent individuals as the senior partner of Slaughter and May".

The statement continues: "Yet, for all this, it is clear on the evidence that Dr Lynch committed a deliberate fraud over a sustained period of time."

Initial allegations of financial impropriety and misrepresentation were made by Hewlett-Packard against Lynch in a press statement in 2012, when it first announced it had made a $5 billion writedown of Autonomy following an internal investigation by HP after the sale.

Clifford Chance is representing Lynch personally in the case, with disputes and regulatory investigations partner Kelwin Nicholls taking the lead. Hussain, the second defendant, is represented by Simmons & Simmons' dispute resolution head Ian Hammond.

Clifford Chance is also acting for Lynch in a separate action in the U.S., where he is facing 14 counts of fraud relating to the sale of Autonomy to HP. These allegations were filed last November (2018). New York white-collar partner Chris Morvillo is leading counsel, alongside U.S. firm Steptoe & Johnson's Reid Weingarten.

Witnesses for the claimants' side are due to provide their evidence to the court during the next nine weeks, beginning today (April 1). The defendants' witnesses will be heard from June onwards. The case is scheduled to finish by the end of this year.

Following the initial fraud allegations, Legal Week sought comment from Slaughters over whether it would continue its association with Lynch.

A spokesman for Slaughters declined to comment on the matter. However, the firm has continued to invest in Luminance – a company that counts the firm and Lynch's venture capital company Invoke Capital as primary investors – and participated in February's £10m Series-B fundraising, maintaining its stake at 5 per cent. Lynch also sits on the Luminance board.

In a 2016 interview with Legal Week, Slaughters' Cooke said the firm's decision to work with Luminance was prompted by a discussion at a lunch meeting with Lynch.

According to Luminance, Lynch offered to step down from the company's board in the past, but his resignation was not accepted by the company.

Luminance would not comment on exactly when Lynch offered his resignation, although Lynch is widely reported to have stepped down from his position as adviser to the UK Government and from board positions on two more companies last December.

CEO of Luminance Emily Foges said in a statement: "Mike is a unique entrepreneur and a tremendous supporter. We look forward to continuing to work with him."