UVA LEDs are used mainly for curing applications, like nail dryers but mostly printing. UVC LEDs are starting to be integrated in water disinfection and purification products. Yole expects that this application will become a major driver of the UV LED market within 3-5 years – and it’s against this background that a new legal battle has broken out.
On 25 July 2018, LG Innotek filed UV LED patent infringement lawsuits against several companies, including Evergreat Inc. and its affiliate companies in the U.S. District Court for the Northern District of California and the U.S. District Court for the Central District of California. This is the first time LG Innotek has filed a patent lawsuit targeting UV LED products.
LG Innotek leads the market with high quality UV LEDs of various wavelengths for curing, exposure, sterilization, and horticulture. Last year, the company demonstrated the power of its proprietary technology by developing UV LEDs for sterilization with the world's best light output of 100 milliwatts.
California-headquartered Evergreat manufactures UV nail dryers, and is well known for its 'MelodySusie' brand. It is also a manufacturer and seller of LED-based decor lights, floodlights and portable lights for outdoor applications.
The patents-in-suit are US Nos. 7,569,865, US No. 7,582,912, US No. 7,785,908, US No. 8,236,585, US No. 8,502,248, US No. 9,209, 360, US No. 9,640,713.
According to the litigation document, Evergreat is using UV LEDs from Epileds in its nail dryers. Epileds is a Taiwanese manufacturer of visible and UVA LEDs. By analysing the patents from Epileds, it appears that Epileds has eight patents, numbers TWI552376, TWI380471, TWI351116, TWI357165, TWI340484, TWI449205, TWM317078 and TWM553495. They are described as similar to LG Innotek patents but only cover Taiwan, while patents from LG Innotek do not cover Taiwan. LG Innotek, even with earlier patents than Epileds' ones, doesn’t yet seem willing to sue Epileds directly at the moment. Suing a US integrator of its LEDs instead has more impact. This litigation can’t be solved with patent cross-licensing, but instead by financial compensation.