SEOUL, July 13 (Xinhua) -- U.S. hedge fund Elliott Associates has filed an investor-state dispute (ISD) suit against the South Korean government over a merger of two Samsung units in 2015, local media reports said Friday.

The U.S. hedge fund claimed compensation of 770 million U.S. dollars from the South Korean government for losses from the 2015 merger between Cheil Industries and Samsung C&T to create the de-facto holding firm of Samsung Group, the country's biggest family-controlled conglomerate.

Elliott, with a 7 percent stake in Samsung C&T, fought against the merger citing unfair terms that it said undervalued the Samsung construction unit.

The National Pension Service, a state-run national pension manager, voted in favor of Samsung's merger despite a controversy over the merger.

According to local media reports, accounting fraud was detected by the financial watchdog in Cheil Industries that overvalued its stake in the biosimilar unit, Samsung Biologics, as well as its land outside Seoul.

By overvaluing the Cheil Industries, it can merge with Samsung C&T, which had a high stake in Samsung Electronics, the crown jewel of Samsung Group, under favorable conditions.

Samsung Electronics Vice Chairman Lee Jae-yong, an heir apparent to the country's biggest conglomerate, was able to get more control over Samsung Electronics with the merger.

The merger was at the center of the corruption scandal, which led to the impeachment of former South Korean President Park Geun-hye. Lee was had put into custody, before being released in February in the appeals court.