Oracle has pegged the value of software downloaded illegally by now-defunct SAP subsidiary TomorrowNow at $4bn.
Initial estimates put Oracle's claim at about $2bn, but in the fourth day of the trial in Oakland, California, former Oracle president Charles Phillips said the licensing for the stolen software would have been worth at least $3bn.
SAP has admitted financial responsibility, but has argued that it should pay only tens of millions of dollars for the infringement, which took place in 2007.
The Oracle figure was set by Larry Ellison, Oracle chief executive, who took the stand as the trial to settle damages entered its second week.
SAP bought TomorrowNow in 2005 and planned to offer support services through the company to lure customers away from Oracle.
Despite the failure of SAP's plan, Ellison emphasised the threat he once believed it posed to Oracle, according to the Financial Times.
"The acquisition of TomorrowNow was a brilliant idea and we were at grave risk, depending on what they did with it," he said.
Ellison said he believed at the time that SAP stood to get between 20% and 30% of Oracle's PeopleSoft customers.
Oracle's lawyers have argued that the scale of the threat should be used to determine what damages SAP should pay.
Oracle says it paid $11bn for PeopleSoft and the loss of customers could have cost it $3.3bn. Oracle is also claiming $600m in damages for loss of Siebel customers.
It is still not known if former SAP head Leo Apotheker will take the stand, as Oracle lawyers have been unable to subpoena him.
The week before the trial began, Ellison issued a statement that he had proof Apotheker knew of TomorrowNow's wrongdoing while it was going on and challenged him to a courtroom showdown.
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