A US appeals court has ruled in favour of chip-packaging manager Tessera in a patent dispute.
On Tuesday the US Court of Appeals for the Federal Circuit upheld a ruling in 2009 by the US International Trade Commission (ITC) that affirmed chip manufacturers Qualcomm, Spansion, ATI Technologies, Freescale Semiconductor and ST Microelectronics had infringed on Tessera's patented methods for semiconductor assemblies.
"Despite years of denials and procedural manoeuvres by Qualcomm, Freescale, ST Microelectronics, ATI and Spansion, the Federal Circuit upheld the ITC's findings that these companies are infringers who have used and profited from Tessera's technology without paying their fair share," Tessera's chief executive Henry Nothhaft wrote in a statement.
Tessera's patents expired on 24 September, 2010, but Tessera "will continue to pursue our right to recover royalties for periods before the patents expired, and believe the Federal Circuit's affirmation will assist our ongoing efforts in the US District Courts", Nothhaft wrote.
The dispute had settled on two Tessera-owned patents — numbers 6,433,419 and 5,852,326 — that outlined a method for packaging semiconductors.
Semiconductor packaging is an industry term for semiconductor assemblies, which are the enclosures that house semiconductor chips and allow them to be connected to electronic circuits.
Tessera made a complaint against the five companies, plus Motorola, to the ITC in 2007, according to an ITC document (PDF). Tessera issued the complaint on the grounds that the companies were violating chip-packaging patents. The company was initially unsuccessful in its application to have its complaints upheld, but after a number of petitions the ITC reversed its decision. On 20 May, 2009 it upheld Tessera's claim that its patents had been infringed.
The ITC brought a "limited exclusion order" into force that amounted to an import ban on certain chips made by the companies.
Both Qualcomm and Spansion have asserted that because the Tessera patents expired on 24 September, 2010, the import ban can no longer be upheld, according to Reuters.
The five companies have 45 days from Tuesday to petition the panel and the Court of Appeals for a rehearing, and have avenues to appeal.
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