South Korea Daily Briefing

Samsung Electronics revealed its zHBM (vertically-stacked HBM) chip at a technical event, claiming an 8x performance improvement over the current HBM3e generation through vertical die stacking — a manufacturing technique that enables dramatically higher bandwidth density within the same power envelope. This matters for the AI chip ecosystem: Nvidia's next GPU generation (Blackwell Ultra and beyond) requires HBM4 with higher bandwidth, and Samsung's zHBM technology is the company's attempt to close the technology gap with SK Hynix, which currently supplies the majority of HBM3e to Nvidia's H-series GPUs. If Samsung's zHBM passes Nvidia qualification testing, the HBM supply concentration risk at SK Hynix would rapidly diminish, compressing SK Hynix's pricing power and margin premium.

Korea's dominant e-commerce operator Coupang reported an operating loss of ₩835 billion (approximately $600M) for Q2 2026, confirming that the company's aggressive logistics network expansion and Rocket Wow membership growth are still consuming capital faster than the business generates margin. For Korean retail sector investors, Coupang's loss profile reinforces the trade-off between market-share capture and profitability that defines the e-commerce cycle — exactly the dynamic US investors faced with Amazon in its growth phase. The concern is timing: Coupang's loss is widening precisely when its public market valuation needs to demonstrate a credible path to breakeven.

A single verbal comment by US Treasury Secretary Scott Bessent on 'excessive KRW volatility' was sufficient to cause an immediate drop in the USD/KRW exchange rate, underscoring how sensitive Korean FX remains to US policy signals. The episode reveals the structural KRW dynamic: with Korea running a large current account surplus and KRW depreciation driven primarily by risk-off capital outflows, any US official signal that the dollar-won relationship is being monitored triggers rapid correction. For KOSPI investors, a stronger KRW reduces Korean exporter earnings in domestic currency terms — Samsung and Hyundai/Kia both report in KRW on USD-denominated exports.