Hewlett-Packard may pursue a claim of up to £2.7 billion ($4.2 billion) according to an economist expected to be called by HP.

Jonathan Orszag, economist at consulting firm Compass Lexecon, said the figure would represent the difference in revenue for HP, before and after the announcement by Oracle that it would no longer port software to HP’s Itanium business in March 2011.

Orszang said that the move to discontinue Itanium by Oracle would continue to impact HP’s business through to at least 2020, with revenue relating to Itanium falling throughout this period.

Orszag said during an evidentiary hearing, that Itanium customers were being put off: “They don't want to have the risk associated with some fight, or some delay, or some issue".

Oracle’s attorneys questioned Orszag’s comments, including the view that HP’s business had not been impacted by other factors, such as the phase out of the Itanium platform by HP, which had become public knowledge.

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