SK hynix jumps 7% after Korea lifts trading curbs

SK hynix shares rose 6.8% to close at 640,000 won (US$447) on December 29, after the Korea Exchange lifted a trading suspension.

The halt, imposed on December 11, was triggered by a rule that stops trading if a stock rises more than 200% year-on-year.

The rule was revised last week to exempt the top 100 stocks on the KOSPI and Kosdaq.

Samsung Electronics shares also rose 2.1%, reflecting broader interest in the semiconductor sector.

Industry officials linked the gains to strong global demand for advanced memory chips, including HBM for AI hardware.

Supply constraints have pushed prices higher, prompting brokerages to raise price targets for both companies.

🧠 Food for thought

Implications, context, and why it matters.

SK hynix holds 62% of High Bandwidth Memory (HBM) 1 and supplies most of Nvidia’s needs 1. That lead hides a pricing turn in 2026.
HBM3e is the latest high-performance version of HBM and costs over four times DDR5, the current server Dynamic Random-Access Memory (DRAM) standard 2. Starting in Q1 2026, DDR5 is expected to earn more profit than HBM3e as rivals squeeze HBM prices and stocks stay ample 2.
That shift will steer makers to devote more lines to server DDR5 2. Deals for DDR5 are set to keep rising through 2026 2.

Cloud providers and enterprise IT teams have a short window to guard against a supply shortfall that lasts into 2026 2. Big new semiconductor fabrication (fab) sites will not ramp until 2027–2028 3.
DDR5 contract prices rose 18–23% in Q4 2025 2. Contract 16-gigabit (Gb) DDR5 chip prices went from $6.84 to $27.20 3. Vendors are still bargaining on Q4 terms 2, so buyers can fix rates before the Q1 2026 profit swing pushes prices higher.
Foundries (contract manufacturers) are juggling AI-focused runs 4 while channel stock fell to 2–4 weeks by October 2025 3. Teams planning 2026–2027 builds should sign multi-year agreements now, before makers shift more lines to higher profit DDR5.