South Korea's antitrust watchdog said Tuesday that it has increased the number of companies on its watch list by nine that limits mutual investments and loan guarantees.

The Fair Trade Commission said the number of corporate affiliates on the list stood at 1,850 that belonged to 63 private business groups and large public companies as of Friday, compared with 1,841 in the previous month.

Twelve companies were added to the list as they were newly created or conglomerates bought stakes in other companies. In addition, three firms were removed due to mergers with affiliates and outright liquidation, the watchdog noted.

Under South Korea's fair trade law, affiliates of large business groups with assets of 5 trillion won (US$4.2 billion) or more are restricted from making equity investments in or offering loan guarantees to one another.

The rule is aimed at preventing the distortion of conglomerate governance structures. (Yonhap News)