KEP
The setup: a neat idea with a messy aftermath
At a seminar in Seoul, Korea University professor Na Hyun-seung laid out a pretty uncomfortable finding for anyone cheering on overlapping listings: the parent company usually doesn’t come out ahead. In a sample of 261 dual-listing cases from 2000 to 2024, parent shares rose 8.94% from the listing review filing date to the day before the listing — then gave a lot of it back after the debut.
The stock price plot twist
According to the study, the average return after the subsidiary listed was:
- 7.58% down after one month
- 9.12% down after three months
- 10.81% down after six months
So if you were hoping the new listing would be a shiny little value machine, the data says: not so fast. The market seems to treat the parent like it’s getting thinner on the margins, not richer.
Why investors should care
The research points to a few reasons this happens:
- Profit double counting can make the overall corporate structure look beefier than it really is
- Liquidity limits on the subsidiary can keep that value from flowing cleanly
- Return of profits gets constrained, which can make the parent look like it’s carrying the heavier backpack
Big picture
This isn’t just an academic hot take — it feeds directly into South Korea’s long-running debate over redundant listings and corporate structure reform. If policymakers tighten the rules, that could reshape how conglomerates think about spinning up listed subsidiaries in the first place.