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9 May 2008


Epistar licenses Rothschild LED patents

LED chip-maker Epistar Corp of Hsinchu Science-based Industrial Park, Taiwan says it has obtained a worldwide license from Dr Gertrude Neumark Rothschild, professor emerita of Materials Science and Engineering at Columbia University, for her US Patents 5,252,499 ('Wide Band-Gap Semiconductors Having Low Bipolar Resistivity and Method of Formation’, issued in 1993) and 4,904,618 (‘Process for Doping Crystals of Wide Band Gap Semiconductors’, issued in 1990), as well as their foreign counterpart patents.

The license agreement follows an investigation instituted on 20 March by the US International Trade Commission based a complaint (‘In the matter of Short-Wave Light Emitting Diodes’) filed by Rothschild alleging infringement by 34 firms of patent 5,252,499 (covering a method of producing gallium nitride-based semiconductors for LEDs and laser diodes emitting in the blue, green, violet and ultraviolet end of the spectrum).

The complaint sought to bar importation into the USA of a wide range of consumer electronics products incorporating infringing devices. These include DVD players using Sony’s Blu-ray format, Motorola Razr phones and Hitachi camcorders, as well as instrument panels, billboards, traffic lights and data storage devices. Other firms cited include Blu-ray DVD player makers Matsushita Electric Industrial Co (Panasonic), LG Electronics Inc and Samsung Group and HD DVD player manufacturer Toshiba Corp, as well as Nokia Corp, Sony Ericsson Mobile, Pioneer, Sanyo Electric Co, and Sharp Electronics.

Under the license obtained by Epistar, customers that have been using or will use LED chips made or to be made by Epistar will be free from any patent infringement assertion under the patents.

Last month, licenses were also obtained by LED makers Everlight Electronics Co Ltd of Taipei, Taiwan and Seoul Semiconductor Co Ltd of Korea.

After previous patent complaints filed elsewhere starting in 2002, LED makers including Germany’s Osram Opto Semiconductors and Japan’s Nichia and Toyoda Gossei have also previously settled with Rothschild over alleged patent infringement. Also, on 10 March, an action that had been brought before the US District Court for the Southern District of New York by Rothschild was settled by LED maker Philips Lumileds of San Jose, CA, USA, giving the firm a non-exclusive license. A separate case against LED maker Cree Inc of Durham, NC, USA is still pending.

See related items:

Seoul and Everlight settle ITC action brought by Rothschild

Seoul Semiconductor agrees license with Rothschild

ITC investigating blue LED/laser patent infringement case

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