By Kwanwoo Jun and Sherry Qin

South Korea's semiconductor titans led a chip rally in Asia that propelled markets higher, buoyed by a labor-dispute settlement at the world's top memory-chip maker and strong quarterly results from AI chip leader Nvidia.

Korea's benchmark Kospi surged more than 8% as Samsung Electronics and SK Hynix--the two largest memory-chip manufacturers in the world--jumped more than 8% and 11% in afternoon trading, respectively. The companies together account for nearly half of the index's total market capitalization.

Korea Exchange briefly halted trading on the Kospi and the smaller, tech-heavy Kosdaq early Thursday to limit volatility, after futures jumped more than 5% and 6%, respectively.

Index heavyweight Samsung's shares got a boost after management reached an 11th hour bonus-pay agreement with union leaders, averting a strike that could have begun Thursday. The union suspended its 18-day walkout plan, with the tentative deal put to a vote for approval from Friday through next Wednesday.

The settlement "should switch investor focus further towards fundamentals" of Samsung, which is set to benefit from additional chip-price hikes amid booming data-server demand, HSBC analyst Ricky Seo said in a note. HSBC raised its second-quarter operating-profit forecast for Samsung by 16%.

Samsung's rally "reflects a normalization in valuations as the company enters a phase of easing concerns over labor-management relations," Shinhan Securities analysts wrote. Investors' expectations for Samsung's higher memory-chip prices, longer-term supply contracts with clients and better shareholder returns have all remained intact, they said in a note.

Shares of Nvidia supplier SK Hynix also rose sharply, after the U.S. AI chip company reported record sales and income overnight, driven by surging demand for data-center computing and the astronomical rise of artificial-intelligence agents.

Net income for the April quarter more than tripled to $58.3 billion as sales soared 85% from a year earlier to $81.6 billion, with both beating forecasts of analysts polled by FactSet.

"This result tells us that AI isn't just a one-year story, it's a story with many years ahead," eToro analyst Josh Gilbert said. "The lens investors should be using from here is that the AI boom still has plenty of runway, but the winners' list is going to get longer."

In Taiwan, another Asian chip-manufacturing powerhouse, the benchmark Taiex ended 3.4% higher, largely driven by gains in semiconductor and AI names.

Shares of Taiwan Semiconductor Manufacturing Co., the world's largest contract chip maker and an index heavyweight, added 2.1%. TSMC is a key supplier of advanced chips for Nvidia.

Foxconn Technology, which builds AI servers for Nvidia, increased 3.1%. MediaTek, a fabless semiconductor company, advanced 9.9%.

Japanese chip stocks also rallied, with Kioxia rising as much as 16% and Renesas Electronics adding up to 11%. Electronics manufacturer Ibiden and chip-testing equipment maker Advantest climbed about 15% and 5%, respectively.

Meanwhile, SoftBank Group jumped 20% after The Wall Street Journal reported that OpenAI, one of its key investments, could file confidentially for an initial public offering as early as Friday.

"While the first steps in AI deployments are around Nvidia chips and the cloud stalwarts, importantly we estimate that for every $1 spent on Nvidia, there is an $8-$10 multiplier across the rest of tech," Wedbush analysts led by Dan Ives said in a note.

--Farah Elias contributed to this article.

Write to Kwanwoo Jun at kwanwoo.jun@wsj.com and Sherry Qin at sherry.qin@wsj.com

(END) Dow Jones Newswires

May 21, 2026 01:55 ET (05:55 GMT)

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