Microsoft is requesting a review of the $290 million patent case successfully brought by i4i in the U.S. Court of Appeals for the Federal Circuit.

Microsoft lost an appeal in a December ruling by a three-judge panel of the court. It is now asking the panel to review its decision or for the case to go before the whole court.

As a result of the decision, the Redmond company has been forced to make changes to Microsoft Word in order to stop selling copies of Word with the infringing XML editing feature. The court's ruling required that to happen by Monday.

I4i, a Toronto software development company, had been awarded $290 million in damages by the U.S. District Court for the Eastern District of Texas. The "grossly excessive" award was the largest ever sustained on an appeal in a patent case, Microsoft said in its review request.

In Friday's request, Microsoft argued two legal points:

• i4i's expert witness testimony was not reliable.


• There was no precedent to rule against Microsoft because the company had made the wrong pre-trial motion.

Here is a statement from Kevin Kutz, a spokesman for Microsoft, on the review request:

"The petition details significant conflicts we believe the Dec. 22 decision creates with established precedents governing trial procedure and the determination of damages, and we are concerned that the decision weakens judges' authority to apply appropriate safeguards in future patent trials.

Microsoft says the custom XML feature that's at issue is little used.

In a separate case in September, Microsoft won an appeal in a patent case with Lucent overturning a $358 million damages award. Friday, Microsoft argued that the i4i ruling contradicts the Lucent ruling.

"That result cannot be reconciled with Lucent, and the conflict between the two decisions will sow confusion among district courts reviewing damages awards on motions for new trials," Microsoft's wrote in its review request. Here is our earlier story on that ruling.

Here is our story on the appeals panel ruling. In this latest move, Microsoft is requesting what's called an en banc review, which would involve all 11 judges of the appeals court.

I have reached out to i4i to see if the company is commenting and will let you know if I hear back.

Update Sunday 10:39 p.m.:

i4i Chairman Loudon Owen put out a statement saying:

"This next step of seeking a rehearing was anticipated. We continue to be confident that we will prevail."