The US Department of Justice (DoJ) has filed a civil suit in a federal court against Oracle, accusing the company of defrauding the federal government by overcharging for software.
The DoJ said Oracle had failed to give the government the same discounts on software as commercial customers, according to the New York Times.
The complaint relates to a contract with Oracle from 1998 to 2006 which required the firm to match discounts made to commercial clients.
The government's complaint includes internal communications at Oracle that show employees discussing how discounts to commercial customers might affect government contracts.
The DoJ case comes after former Oracle employee Paul Frascella acted as a whistle-blower in May 2007 and made a similar complaint against Oracle.
The federal government said it would investigate the matter and has now joined Frascella's complaint.
The government could receive up to three times the damages it incurred and will pursue the case through the civil division and the US attorney's office in the Eastern District of Virginia.
Oracle has declined to comment, the report said.