Samsung Display has sued China’s BOE over patent infringement of multiple technologies related to OLED (organic light-emitting diode) panels.

Samsung Display’s first legal action against BOE comes as Korea’s dominance in the OLED panel industry is being chipped away by Chinese producers offering panel-making technology at a cheap price.

The complaint filed with the Texas Eastern District Court last week by Samsung Display said BOE infringed on Samsung Display’s five OLED panel-related technologies including the so-called Diamond Pixel which is considered the Korean panel maker’s key technological asset.

This technology refers to the placement of red, green and blue-colored sub pixels in a diamond shape, enabling higher resolution compared to the traditional square structure.

Samsung Display did not issue an official statement on the lawsuit filed against BOE.

The dispute between the two companies was initiated last year when Samsung Display sent a letter to BOE, stating they were making and selling OLED panels that are infringing on Samsung’s patented technology.

BOE chose to ignore it.

Samsung Display took further action in December by filing a complaint with the U.S. International Trade Commission, that more than a dozen iPhone repair shops in the U.S. were using BOE’s OLED panels that were made with Samsung’s proprietary technology.

Regardless, BOE continued to manufacture and sell the OLED panels in question and also promoted them at business fairs and trade shows. BOE exhibited the OLED panels at The Society for Information Display’s DisplayWeek, one of the industry’s major trade shows, in 2018, 2019 and 2022.

BOE’s counterattack then ensued.

Early this year, BOE and three other Chinese panel makers requested a patent invalidation trial against Samsung Display in the U.S.

BOE also made a counterclaim against Samsung Display with the Chongqing No. 1 Intermediate Court in May that their OLED panel technology is in fact breached by the Korean company.

Korea’s leadership in OLED panels, especially the small and midsized ones for electric gadgets, was previously dominate.

That trend is changing fast with Chinese panel makers in close pursuit of Samsung Display and LG Display’s technology armed with better price tags.

China has already done so once with LCD (liquid crystal display) panels in 2021 when it toppled Korea from the No. 1 spot it had for more than a decade. It led Samsung Display and LG Display to either suspend or downsize its LCD business and veer their focus on more expensive and advanced OLED panels.

Korea’s market share for small and midsized OLED panels which used to stand at 88.1 percent in 2019 tumbled to 79.1 percent, according to statistics provided by Korea Display Industry Association.

However, China’s share expanded from 11.1 percent to 20 percent during the same period.

BY JIN EUN-SOO [jin.eunsoo@joongang.co.kr]