The nation's antitrust regulator has named secondary battery materials manufacturer EcoPro as one of eight business groups added to the list of conglomerates subject to tighter supervision.

The Fair Trade Commission said Tuesday the designation will come into effect on May 1 and the number of conglomerates subject to public disclosures this year stands at 82, comprising three-thousand-76 affiliates.

EcoPro, a leading producer of secondary battery materials, has joined the list as its assets surged by more than two trillion won, or some one-point-five billion U.S. dollars, in the past year to become the 62nd largest conglomerate.

Steelmaker POSCO rose to number five, outpacing Lotte Group.

Hyundai Marine & Fire Insurance Company and Iljin Group have been dropped from the list due to a decline in assets while LX, a spin-off from LG Group, is among the new entries.

Under domestic law, corporate groups with assets of over five trillion won are obligated to disclose a detailed status of their business.