Intel had asked the court to reconsider its decision of 11th October, which found that the Itanium chips infringed upon two "valid and enforceable" patents owned by Intergraph covering parallel instruction computing.
In his final judgement, however, Judge T. John Ward of the US District Court for the Eastern District of Texas confirmed the earlier decision, citing nine cases of patent infringement by Intel's Itanium chips. The world's biggest chip maker has now 30 days to appeal the ruling.
Intel reportedly said it would challenge the decision before the US Court of Appeals for the Federal Circuit in Washington, DC.
Under a previous agreement between the two sides, Intel would pay Intergraph $150 million if it lost a motion for reconsideration of the 11th October ruling.
If Intel wins on appeal, it will pay nothing and license the technology covered by the Intergraph patents. If it loses the appeal, it will have to pay an additional £100 million to license the patents.