WASHINGTON - A U.S. appeals court on Monday threw out a $2.18 billion patent-infringement award won by patent owner VLSI Technology against Intel Corp, overturning one of the largest verdicts in the history of U.S. patent law.

The U.S. Court of Appeals for the Federal Circuit reversed the jury's 2021 verdict that Intel infringed one VLSI patent, and sent the case back to Texas for a new trial to determine how much Intel owes for infringing a second VLSI patent.

Patent holding company VLSI is owned by investment funds managed by Fortress Investment Group. Abu Dhabi's Mubadala Investment Co agreed to acquire a majority share of Fortress from Japan-based Softbank Group Corp this year.

Representatives for Intel and VLSI did not immediately respond to requests for comment on the decision.

VLSI has sued Intel in multiple U.S. courts, accusing it of infringing several patents covering semiconductor technology.

A jury in Waco, Texas awarded VLSI $2.18 billion in the first trial from the dispute. The jury found that technology in Intel microprocessors infringed patents that VLSI had acquired from Dutch chipmaker NXP Semiconductors.

The Federal Circuit on Monday ruled that there was insufficient evidence for the jury to have found that Intel infringed one of the two patents at issue, which had accounted for $675 million of the verdict.

The Washington-based appeals court affirmed that Intel infringed another VLSI patent, but said that problems with the damages analysis justified a new trial to determine the proper award.

The jury had awarded VLSI $1.5 billion in damages for Intel's infringement of the patent.

Intel stock was down more than 4% on Monday morning. Other major chipmakers were also seeing declines.

Intel defeated VLSI's bid for more than $3 billion in damages in another Waco jury trial later in 2021. A separate jury in Austin, Texas decided that VLSI was entitled to nearly $949 million from Intel in a third patent case last year.

The companies later agreed to dismiss another potential multi-billion-dollar case in Delaware. Another trial in Northern California is set to begin in 2024.

  - Reuters