South Korea's corporate watchdog said Thursday seven more major firms are required to disclose detailed information on their management and business activities.

The Korea Fair Trade Commission (KFTC) unveiled its new updated list of large business groups with assets of 5 trillion won ($4.5 billion) or more to face tougher filing regulations.

The number of such firms stood at 71, with e-commerce giant Coupang, Korea Aerospace Industries Co. (KAI), the country's sole aircraft manufacturer, and six others newly added to the list.

It also placed 40 conglomerates with assets of 10 trillion won or more on its list of companies under supervision for their equity investments or inter-affiliate loan guarantees. This was also higher than 34 big firms under scrutiny a year earlier.

Under the fair trade law, large business groups with assets exceeding 5 trillion won are required to publicly file their business information, and those with 10 trillion won in assets or more are banned from making equity investments among affiliates or offering loan guarantees to each other.

The watchdog said the number of firms subject to tighter regulations increased as the value of their assets, such as stocks and property, sharply rose, driven by liquidity unleashed in the process of tackling the pandemic.

In the latest update, the country's largest family-run conglomerate Samsung Group has the biggest assets at 457.3 trillion won, and 59 affiliates under its wing.

Automaking group Hyundai Motor Group ranked second with 246 trillion won in assets, followed by energy-to-telecom giant SK Group with 239.5 trillion won. (Yonhap)