SK Hynix Hits $1 Trillion: Inside the Cooling Tech, ETF Frenzy, and Insider Trading Rules Driving the Rally

SK Hynix issues insider trading alert for leveraged ETFs amid record stock rally, unveils iHBM cooling for Nvidia, and posts Q1 2026 profit surge.

SK Hynix has placed its executives on formal notice just as the stock touched rarefied territory. Ahead of the debut of single-stock leveraged ETFs on Wednesday, the memory chipmaker warned top management that the same strict insider trading rules governing direct share purchases now apply to transactions in these new products, which were set to begin trading on Thursday. The move, required under Korea’s Financial Investment Services and Capital Markets Act, subjects such trades to disclosure obligations and signals the company’s deepening focus on compliance as retail demand explodes.

The new ETFs, which offer twice the daily return of SK Hynix’s stock, opened with a bang. On their first day, some of the products surged roughly 24%, triggering multiple volatility halts and overwhelming servers at financial education platforms. The debut coincided with a blistering rally in the underlying equity: SK Hynix shares jumped as much as 15% to touch a record 2.28 million won, pushing its market capitalisation past $1 trillion for the first time — roughly 1.624 trillion won, or about $1.08 trillion. The stock has now soared 248% since the start of the year and has more than quadrupled from its October 2025 low of around 510,000 won.

Cooling down the heat inside its chips is the next big bet. SK Hynix unveiled its integrated HBM cooling solution, dubbed iHBM, which embeds heat-dissipating elements — called ICEs — directly into the package’s lowest die-to-die layer, where thermal concentration is highest. The company claims the design cuts thermal resistance by more than 30% compared with conventional HBM, keeping performance stable even under extreme loads. The technology is targeted at Nvidia’s upcoming Rubin Ultra accelerator, which can draw up to 230 kilowatts per rack — 64% more than the current Blackwell GPU — and for the next-generation “Feynman” platform. iHBM will be introduced from the eighth HBM generation, HBM5, and can be manufactured using existing mass-production packaging processes.

The strategic timing is no accident. SK Group Chairman Tae-won Choi is scheduled to meet Nvidia CEO Jensen Huang in Taipei on the sidelines of the GTC Taipei 2026 conference, held alongside Computex. Huang will deliver a keynote on June 1, one day before the official fair opening. The talks are expected to cover HBM progress, and Choi may also sit down with TSMC Chairman C.C. Wei to cement the trilateralsupply alliance. Huang has already flagged rising memory costs as a form of “very important inflation” that could significantly affect consumer electronics prices, putting direct pressure on SK Hynix, Micron, and Samsung to expand capacity.

The fundamentals behind the valuation are staggering. In the first quarter of 2026, SK Hynix posted a consolidated operating profit of 37.61 trillion won — nearly double the prior quarter and up 405.5% year-over-year — on revenue of 52.58 trillion won. Net profit reached 40.35 trillion won. The company controls roughly 57% of the global HBM market by fourth-quarter 2025 revenue, and its production capacity for specialised AI memory is effectively sold out for the next three years. Customers have offered to finance new fabrication lines or buy expensive lithography tools just to secure supply.

Yet a fierce debate is raging over whether this memory supercycle can sustain itself. Bulls argue that artificial intelligence has killed off the industry’s historic boom-bust rhythm, pointing to structural DRAM shortages. Citigroup forecasts DRAM prices could rise up to 200% in 2026, and UBS sees a supply bottleneck lasting at least through the first quarter of 2027. Nomura is even more bullish, projecting the stock could hit 4 million won within 12 months — roughly double current levels.

Sceptics, however, warn that history tends to repeat. William de Gale, a portfolio manager at BlueBox Asset Management, told CNBC the memory sector is “a pretty terrible industry over the long term” because of its enormous cyclical swings. The tension between structural change and deep-rooted volatility is now the central question hanging over SK Hynix’s valuation — even as the stock sits at 2.243 million won, precisely at its 52-week high, and the company braces for a new wave of leveraged trading that its own executives have been told to treat with caution.