Samsung Displayhas filed a lawsuit against LG Display over patents related to OLED displays.

In the suit filed on Monday with a local intellectual property tribunal, Samsung claimed that seven patents held by LG Display are invalid as they "lack innovation," according to the Yonhap News agency.

Last September, LG Display filed a suit against Samsung over an alleged violation of its OLED patents, claiming that Samsung's five products, including the Galaxy S-series smart phones and tablet computer Galaxy Tab, infringed on its patents.

In July, researchers at Samsung and board members at LG Display had been charged over the theft of OLED display technology, with information related to the production of larger sized OLED displays.

OLED displays emit light rather modulating a backlight. As such the display is bright, shows rich saturated color and is thinner than liquid crystal display (LCD) as it does not need a backlight.