SK Hynix's Chairman Breaks a Career-Long Habit Just as the Market Needed a Signal

SK Hynix chairman's timely share purchase preceded a 30% daily surge, as record Q2 earnings and an Nvidia partnership reignite AI chip optimism.

The timing was almost too perfect. After weeks of punishing losses that wiped more than 40 percent off SK Hynix's share price, the company's chairman stepped into the market for the first time in his career and bought his own stock. By the close of trading in Seoul on Friday, the semiconductor giant had surged to 1,718,000 KRW — up 29.95 percent on the day and hitting the daily trading limit in the process.

The purchase itself was modest in size: 3,620 common shares acquired on July 30 at the prior day's closing price of 1,322,000 KRW, amounting to roughly 4.79 billion KRW, or about 3.3 million euros. But the deliberate scale of the transaction has drawn attention. Market observers note that had Chey Tae-won spent more than 5 billion KRW, he would have been required to file a 30-day advance notice with regulators. By keeping the buy beneath that threshold, the SK Group chairman was able to signal his confidence immediately, without delay.

A Rally With Roots in Both Seoul and Silicon Valley

The explosive Friday session didn't happen in isolation. Momentum had been building since Thursday, when the Philadelphia Semiconductor Index jumped 8.19 percent following strong quarterly results from major US tech companies. SK Hynix's US depositary receipts responded overnight with a 17.52 percent gain, setting the stage for the Seoul rally.

The broader South Korean market joined in the enthusiasm. The KOSPI index climbed 18 percent as investors rotated back into semiconductor names, with SK Hynix leading the charge.

Record Numbers That Initially Fell Flat

The irony of the recent sell-off is that it followed what should have been a triumphant earnings report. SK Hynix posted second-quarter 2026 results on Wednesday that showed revenue soaring 257 percent to 79.32 trillion KRW and operating profit jumping 557 percent to 60.54 trillion KRW. The operating margin of 76 percent marked an all-time high for the memory chip maker.

Net profit reached 93.92 trillion KRW — more than twelve times the year-ago figure. But a substantial portion of that bottom line came from non-operating sources: 63.3 trillion KRW stemmed from revaluations and sales of equity stakes, most notably the company's holdings in Japanese chipmaker Kioxia.

Despite the headline numbers, the stock initially came under pressure. Analysts had been looking for revenue closer to 84 trillion KRW, and the combination of missed estimates plus questions about the sustainability of one-off investment gains weighed on sentiment. The shares had fallen more than 40 percent from their June record high of 2,987,000 KRW in the week before Chey's purchase.

The Nvidia Factor and a Pivot to DDR5

The market's about-face was reinforced by the fundamental story that had driven SK Hynix's ascent in the first place. On July 24, at the AI Summit in San Francisco, the company cemented a strategic partnership with Nvidia valued at an estimated $500 billion. The multi-year alliance covers joint development of next-generation AI memory chips and construction of a 2-gigawatt AI factory slated to come online in 2027.

Meanwhile, mass shipments of HBM4 — the sixth-generation high-bandwidth memory — have begun. SK Hynix has locked in long-term supply agreements with roughly ten major global customers, securing revenue visibility for the next five years. The company is also shifting production capacity toward DDR5 memory, where severe supply shortages have pushed margins as high as 90 percent.

With approximately 88 trillion KRW in cash reserves at the end of the quarter, SK Hynix plans to expand production at its Yongin and M15X facilities to meet AI demand through 2027.

A Stock Still Recovering Ground

Even after Friday's dramatic advance, the shares remain 44.63 percent below their 52-week high. But the year-to-date gain of 154.58 percent underscores just how central SK Hynix has become to the global AI infrastructure buildout. The combination of a chairman's personal vote of confidence, a landmark Nvidia partnership, and the ramp of HBM4 deliveries gives the company a compelling narrative — though whether the current pace can be sustained will depend on the quarters ahead.