SK hynix (SKHY) shares soared 5.09% over a 24-hour period in after-hours trading on Tuesday, as investors reacted to the company's blockbuster second-quarter earnings report that underscored the explosive growth in AI-related memory chip demand.

The South Korean memory giant reported record quarterly revenue of 79.3 trillion won, surging 257% year-over-year, while operating profit skyrocketed 557% to 60.5 trillion won—the highest in the company's history. The stellar performance was fueled by robust sales of high-value products such as HBM, server DRAM, and enterprise SSDs, driven by sustained investments in AI infrastructure from major technology companies.

Although the results slightly missed elevated analyst expectations—with the market forecasting operating profit of approximately 64.2 trillion won—investors appeared to focus on the company's bullish outlook. SK hynix confirmed it has secured long-term agreements with around ten key customers and is ramping up mass production of its next-generation HBM4 chips, reinforcing confidence in the sustainability of AI-driven memory demand.