Samsung Electronics Co. (005930.SE), the world's biggest supplier of liquid-crystal-display panels by sales, said Thursday it filed a complaint with the U.S. International Trade Commission against AU Optronics Corp. (AUO) on June 1, alleging the Taiwan-based electronics company and its customers imported and sold LCD devices that infringed a number of Samsung patents.

Samsung is increasingly using the courts to seek protection for its patents as own-brand products have become a bigger part of its business. Such lawsuits are common in the highly competitive technology industry, with global electronics makers looking to protect their patents for products such as flat panel displays, handsets and televisions.

AUO spokeswoman Yawen Hsiao said: "We are reviewing the matter and will take the necessary action to protect the interest of our company and of our customers."

The AUO customers who infringed Samsung's patents are Sanyo Electric Co. (SANYY), Acer Inc. (2353.TW) and a Taiwan-based electronics maker BenQ Corp, Samsung spokesman Nam Ki-yung said. An Acer spokeswoman declined to comment and a Sanyo Electric spokesman in Tokyo also declined to comment, saying the company hasn't yet confirmed whether it has been sued by Samsung. BenQ was not immediately available for comment.

Samsung said it also filed a suit against the Taiwanese company in the U.S. District Court of Delaware with the same allegations as in the complaint to the trade commission.

"In the USITC complaint, Samsung seeks an order prohibiting the import and sales of these infringing LCD devices, which are used in numerous LCD televisions, LCD monitors, and notebooks with LCD screens," Samsung said in a statement.

"Samsung's Delaware complaint seeks damages associated with infringement of Samsung's asserted patents."

Separately, Samsung is also seeking damages associated with alleged infringement by AUO and some of its customers of two additional Samsung patents.

Samsung spokesman Nam Ki-yung said the firm has also asked the Northern District of California for a legal judgement that certain AUO-owned patents aren't infringed by any Samsung products.

"AUO hasn't filed any lawsuits against Samsung for now, but there was talk that AUO is insisting that Samsung had infringed some of their patents over LCD technologies," the spokesman said.

-By Jung-Ah Lee, Dow Jones Newswires; 822-3700-1907; jung-ah.lee@dowjones.com

--Juro Osawa in Tokyo and Lorraine Luk in Taiwan contributed to this story.