Leveraged ETF reversal tests Korea’s regulatory credibility

South Korea's abrupt reversal over single-stock leveraged funds has revived a broader question for global investors: whether unpredictable policymaking itself contributes to the country's long-standing equity market discount.

The speed with which authorities moved from approving the products to tightening the rules — amid conflicting comments from senior officials — has turned the episode into a test of regulatory credibility.

The concern is not that regulators strengthened safeguards for high-r ...