Korea’s liquidity squeeze is feeding the won’s slide

Korea’s liquidity squeeze

The won is not simply weakening because the dollar has found its feet again. Korea has become a market where an equity boom, crowded ownership, FX hedging and short-term funding stress are all pulling on the same rope, and lately they have been pulling in the wrong direction.

USD/KRW has pushed higher for four straight sessions, but the more interesting story sits beneath the surface. Overseas investors have been selling Korean equities aggressively, with industry estimates pointing to roughly $30 billion of equity outflows during June after another $27 billion in May. That is a serious amount of pressure for any currency to absorb, particularly when the selling is being driven less by a change in Korea’s export outlook and more by the mechanical consequences of a market that has become heavily concentrated in two semiconductor giants.

Samsung and SK Hynix have become such dominant weights in Korea’s equity indices that they are now pressing well above common single-stock concentration thresholds. The market’s success has become the source of its own friction. As the two names rise, passive funds, benchmarked investors and hedge funds with internal risk limits are forced to trim exposure, not because they have suddenly turned bearish on Korean technology, but because the position has become too large to hold comfortably.

That is the first turn of the screw. The second comes through the FX hedge.

Foreign investors own a vast pool of Korean equity exposure, and as the KOSPI surged through the second quarter, the amount of won risk sitting inside those portfolios expanded sharply. Even a modest hedge ratio creates a large amount of demand for offshore dollar hedges when the underlying equity market is rising by this much. Much of that hedging is done through the illiquid NDF market, where the demand is often most intense around quarter-end, when passive and real-money investors tend to rebalance in bulk rather than continuously.

In other words, Korea has been dealing with a peculiar problem: the stronger its semiconductor rally became, the greater the structural demand to sell won became. It is the financial equivalent of a carnival ride spinning too quickly. The crowd is still cheering, but the safety harnesses are beginning to strain.

The liquidity story then made matters worse.

Local securities firms have had to fund a sharp rise in retail margin activity and leveraged single-stock ETF exposure. Those products require dealers to hedge, post futures margin and continuously manage financing needs as volatility rises. Local reports suggest commercial paper and short-term bond issuance by securities firms has surged, with the sector accounting for an unusually large share of short-dated issuance in recent months.

That funding strain becomes more acute when the won weakens and Korean government bonds sell off at the same time. Securities firms facing offshore counterparties on total-return swaps can find themselves caught in a three-way squeeze: equity-related margin requirements are rising, collateral values are declining in dollar terms and domestic funding costs are moving higher. The result is more borrowing demand in won at precisely the point when liquidity is already becoming scarce.

This is why the widening gap between offshore NDF pricing and onshore FX swaps matters. It suggests the market is not merely trading a directional view on the won. It is beginning to price the cost of carrying and hedging Korean exposure through a tighter funding environment. As those pressures rise, arbitrage trades between the onshore and offshore markets become harder to maintain, which can leave NDF points elevated for longer than traders initially expect.

The near-term outlook is therefore awkward for the won. If Samsung and SK Hynix continue to lead the KOSPI higher, more concentration-driven rebalancing could keep generating equity outflows and offshore dollar hedging demand. If the equity market falls, the hedge unwind may offer some relief, but broader portfolio outflows could easily offset that support. The cleaner path for sustained won strength may require something more dramatic: enough of a correction to bring index weights back below concentration limits, followed by a stabilisation that attracts fresh inflows rather than forced selling.

That leaves Korean policymakers trying to manage speed rather than direction. Exporter dollar selling should provide some support as overseas earnings rise, but conversion is already relatively high and may struggle to offset the scale and volatility of equity-related flows. With the Bank of Korea expected to keep a tightening bias and local funding demand still elevated, the pressure on NDF points may persist even if spot moves become more orderly.

For now, the won is caught in the shadow of Korea’s own equity success. The rally created wealth, but it also created concentration. Concentration created rebalancing. Rebalancing created hedging. Hedging collided with a leveraged domestic market already hung for funding.

The result is a liquidity squeeze that looks less like a normal FX selloff and more like a market trying to breathe through a narrowing straw.