LED producer Seoul Semiconductor Co Ltd (SSC) of South Korea, along with its affiliate Seoul Viosys Co Ltd, have filed a patent infringement complaint in the US District Court for the Central District of California against retail firm Kmart Corp. Kmart Corp. owns about 1000 stores in the USA and earns annual revenue of about $25 billion. Seoul Semiconductor claims that Kmart is selling LED products that infringe eight patents.
The Seoul Semiconductor patents cover LED technologies including LED epitaxial growth, LED chip fabrication, multi-chip mounting technology, high-CRI (color rendering index) enhancement with phosphor combinations, omnidirectional LED lamps, and Acrich MJT (multi-junction technology). In the infringement complaint, Seoul Semiconductor accuses Kmart of selling infringing products including an LED filament bulb for replacement of traditional incandescent bulbs.
One of the asserted patents was invented by professor Shuji Nakamura, the winner of the 2014 Nobel Prize in Physics for his participation in blue LED development. Dr. Steven DenBaars, co-invented another of the patents. Dr. DenBaars serves as a professor of Materials and Electrical and Computer Engineering at the University of California, Santa Barbara (UCSB).
Seoul Semiconductor points out that it has consistently succeeded in patent enforcement actions since its case against Taiwan-based AOT Inc in 2003. For example, in 2015, the company filed patent infringement complaints against multiple North American TV manufacturers, ending in a judgment for infringement and or payments for past damages. Already in 2016, Seoul Semiconductor won a unanimous jury verdict against Japanese LED lens maker Enplas. The jury held, and the US district court upheld a finding that Enplas willfully infringed Seoul Semiconductor’s patents and is liable for $4m.
Seoul Semiconductor subsidiary, Seoul Viosys has also pursued legal action for patent infringement, leading to a judgment of infringement, payments for past damages, and a royalty-bearing license against a US-based UV LED curing device maker. Recently, Seoul Viosys filed an additional patent infringement lawsuit against a maker of a UV LED-based insect trap in the USA.
“We have invested tremendous resources for environment-friendly technology innovation for 25 years, and as a result we have successfully commercialized various kinds of the first-developed technologies,” says Ki-bum Nam, VP of the lighting business department at Seoul Semiconductor. “To create a fair market competition, we continuously take any and all actions necessary to deter such infringement and protect our intellectual property.”