AFP - A US District Court judge has ruled that a Xerox Corp patent was infringed upon by Palm Inc and 3Com Corp in their handheld electronic organisers using Graffiti, Xerox said Thursday.

Graffiti is a simplified pen-based method of entering data into computing devices.

The decision by Judge Michael Telesca of the US District Court for the Western District of New York, ends the liability portion of the case, clearing the way for Xerox to seek damages in the next phase of trial.

The trial court will determine the amount of damages for past infringement of the patent and Palm's ability to continue to use the technology, Xerox said in a statement.

If the infringement was willful, the court can triple the amount of damages due to Xerox.

Both Palm and 3Com are jointly and separately liable.

"Either Palm will have to cease production of its handheld organiser or licence the technology from Xerox," said Christina Clayton, Xerox general counsel, in a statement.

In April 1997, Xerox sued US Robotics, later acquired by 3Com, claiming that the handwriting recognition technology marketed as Graffiti and used in Palm handheld devices infringed a Xerox patent received on January 21, 1997.

The technology in question, known as Unistrokes, was invented at Xerox's Palo Alto Research Centre.

Palm spokeswoman Marlene Somsak said the company could not immediately comment because it was still reviewing the ruling.

©AAP 2001