What is the 5% rule (large shareholding report)?

Under this system, a person who, together with specially related persons, comes to hold 5% or more of a listed company's shares or similar securities, or whose holding subsequently changes by 1% or more or whose purpose of holding changes, must report to the Financial Services Commission and the Korea Exchange within 5 days from that date.

It covers not only legal ownership but also cases of substantive control, and it also applies to securities that can become shares, such as convertible bonds. Investors can check changes in major shareholders' stakes through the disclosures.