The global AI rally has driven Samsung Electronics and SK Hynix to record highs
this year but exposed structural fragility in the KOSPI. The two stocks now
account for a record c.60% of the KOSPI's market-cap weighting, up from roughly
40% two years ago. After a sharp sell-off last week, regulators suspended twice
KOSPI trading to stabilize markets; plans to launch large-cap options including
SK Hynix have been delayed. Reports that retail investors bought Samsung and SK
Hynix with borrowed funds raise margin-call risk, and the concentration could
prompt institutional de-risking that would amplify downside. Baosheng's head of
equity research Mathieu Rashet said recent moves are a clear reminder of
concentration risk and that crowded positions make high volatility likely.