SKHX Adds 6.54% as the Seoul Reopen Narrows SK Hynix's 25% ADR Premium

The Reverse Kimchi Premium

SK Hynix has two official prices now, and a third that only exists on Hyperliquid. The Nasdaq ADR (ticker SKHY) closed Friday at $154.03, while the Seoul shares it represents sat at 1.842 million won — a roughly 25% "reverse kimchi premium" of the US line over the home stock. At the 10-ADS-to-one-share conversion ratio, that $154 ADS implies about $1,540 per common share. SKHX, which tracks a single Seoul-listed share, is marking $1,232 — right in line with Korea, and about 25% below where the US market values the same equity. The gap is not noise: it ballooned toward 50% on July 14 when the ADS printed $193.92, then began compressing as arbitrage expectations built.

Why Seoul Got Hit Harder

The premium is really a story about which side sold off. SK Hynix's US debut was a blowout — the largest-ever US listing by a foreign company, $26.5 billion raised, priced at $149 and closing its first session up 13% at $168.01. Then Seoul got the hangover. Home shares posted their worst single session on record, down about 15% on July 13, after a Korea Investment & Securities note pegged Q2 operating profit near 60.4 trillion won — up 556% year over year, but roughly 8% under the ~65 trillion consensus — and cut its blended DRAM ASP growth estimate from 50% to 28.9% quarter over quarter, with full HBM4 mass production slipping into Q3. The ADR, propped up by US option flows, fell far less. That asymmetry is the entire gap. The read Korean desks keep citing is the TSMC precedent: when an ADS premium runs past 20%, the home shares tend to be the cheap side, not the ADR the expensive one.

The Perp Is Pricing the Convergence

This is where the perp earns its keep. With both Seoul and the Nasdaq dark from Friday's close through the weekend, SKHX was the only venue where SK Hynix actually traded — and it added 6.54% over 24 hours into Monday's Seoul reopen on roughly $349 million of perp volume. That is the perp doing exactly what it should: front-running the moment Korean price discovery switches back on. We already have a taste of how violent the catch-up can be — when the premium spiked, home shares jumped 13.49% intraday on July 15 to narrow it. The hard deadline is July 29, when two-way ADR-to-local conversion opens — existing ADRs can convert to local shares freely, while new ADR issuance from local shares stays capped — on the same day SK Hynix reports Q2 earnings. Underneath the arbitrage, the fundamental case hasn't moved: the company still controls about 58% of the HBM market and is shipping 12-layer HBM4 to Nvidia. The question isn't whether the business is good — it's which quote, Seoul or the ADR, is telling the truth before July 29 forces them together, and the perp is the cleanest way to bet on that convergence.