KOSPI tumbles as Democrat sweep fuels AI infrastructure concerns

Korean stocks plunged in Seoul Thursday after Democratic victories in the U.S. midterm elections raised concerns about tighter oversight of AI and data center development. The KOSPI closed at 5,383.80, down 5.28 percent, as Samsung Electronics and SK hynix led a semiconductor sell-off. Korean drugmakers and biotech companies rose on expectations of policies supporting lower-cost medicines and clean energy. Kiwoom Securities analyst Han Ji-young said projects already underway were unlikely to face major delays, and the won weakened to 1,342.1 per dollar.

The KOSPI opened at 5,580.09, down 1.82 percent from its previous close, and stayed in negative territory throughout the session.

SK hynix fell 9.46 percent to 1.26 million won, while Samsung Electronics dropped 7.57 percent to 201,500 won.

Celltrion gained 7.5 percent, Hanmi Pharmaceutical rose 9.8 percent and Samsung Epis Holdings surged 14.33 percent.

On the Kosdaq, LigaChem Biosciences rose 7.41 percent and Alteogen gained 3.68 percent.

The won weakened 0.6 won against the U.S. dollar to close at 1,342.1 won.

Published Nov 5, 2026 4:26 pm KST

A stock ticker at Hana Bank's headquarters in Seoul shows the shares of Korea's two semiconductor heavyweights, Thursday. SK hynix plunged 9.46 percent to 1.26 million won, while Samsung Electronics tumbled 7.57 percent to close at 201,500 won. Yonhap

Korean stocks plunged Thursday, as concerns over tighter U.S. regulation of artificial intelligence (AI) and data center development triggered a broad sell-off in semiconductor shares following sweeping Democratic victories in the midterm elections.

The benchmark KOSPI opened at 5,580.09, down 1.82 percent from the previous close, according to the Korea Exchange. It remained in negative territory throughout the session, eventually closing at 5,383.80, down 5.28 percent.

The decline was driven largely by a rout in Samsung Electronics and SK hynix, the country’s two semiconductor heavyweights, which together account for roughly half of KOSPI’s market capitalization. Their outsized weight left the index particularly vulnerable to a shift in sentiment toward the chip sector.

SK hynix plunged 9.46 percent to 1.26 million won, while Samsung Electronics tumbled 7.57 percent to close at 201,500 won.

The weakness in Korean chip stocks followed a sell-off in related U.S. shares overnight. Nvidia fell 3.17 percent, while chipmakers Micron and SanDisk lost 7 percent and 7.91 percent, respectively, amid concerns that a tougher regulatory environment could slow the expansion of AI infrastructure.

The U.S. midterm elections led to a historic Democratic sweep, with the party taking control of both the Senate and the House of Representatives. The result raised concerns that a Democratic-led Congress could pursue stricter oversight of AI development and investment, while political support for expanding data center infrastructure could become less certain.

Investors are particularly concerned that delays in data center construction could prompt major cloud-computing companies to reassess the timing of planned investments. That, in turn, could cloud the outlook for demand for high-bandwidth memory and other advanced chips supplied by Korean manufacturers.

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The election outcome, however, has also created potential opportunities for other sectors, particularly renewable energy and pharmaceuticals.

Shares of Korean drugmakers and biotech companies rallied on expectations that Democrats would push ahead with policies aimed at lowering health care costs and supporting clean energy.

On health care, the party’s policy agenda includes efforts to preserve Medicaid funding and expand government assistance for health insurance, potentially creating a more favorable environment for lower-cost alternatives to branded medicines.

Korean biosimilar makers could benefit if U.S. efforts to rein in drug spending encourage wider adoption of biosimilars, which offer comparable benefits to original biologic medicines at lower prices.

Celltrion rose 7.5 percent from the previous session, while Hanmi Pharmaceutical gained 9.8 percent and Samsung Epis Holdings surged 14.33 percent.

Biotech shares also outperformed on the secondary Kosdaq bourse, with LigaChem Biosciences rising 7.41 percent and Alteogen gaining 3.68 percent.

Supporters celebrate during a midterm election night watch party for Texas Democratic Senate candidate, State Rep. James Talarico, Tuesday, in Austin, Texas. AFP-Yonhap

“Concerns over potential delays in new data center projects could widen the gap between AI-related stocks, such as semiconductors and power equipment, and non-AI sectors like secondary batteries and solar,” said Han Ji-young, an analyst at Kiwoom Securities.

Still, she expects the impact on chipmakers to be limited, as data center projects already underway are unlikely to face major delays, leaving existing supply contracts and earnings forecasts for AI infrastructure companies largely intact. She added that nationwide restrictions would be difficult to implement, given the president’s veto power, differing views within the Democratic Party and Washington’s determination to maintain its lead in AI.

In the Seoul foreign exchange market, the won weakened 0.6 won against the U.S. dollar to close at 1,342.1 won.

周四，韩国股市在首尔暴跌，此前美国中期选举民主党获胜引发了人们对人工智能和数据中心开发监管力度加大的担忧。韩国综合股价指数（KOSPI）收于5383.80点，下跌5.28%，三星电子和SK海力士领跌半导体股抛售潮。受市场预期政府将出台支持低成本药品和清洁能源的政策，韩国制药和生物技术公司股价上涨。Kiwoom证券分析师韩智英表示，已在进行中的项目不太可能出现重大延误，韩元兑美元汇率跌至1342.1。

韩国综合股价指数（KOSPI）开盘报5580.09点，较前一交易日收盘下跌1.82%，并在整个交易日内保持下跌趋势。

SK海力士股价下跌9.46%至126万韩元，三星电子股价下跌7.57%至201500韩元。

Celltrion股价上涨7.5%，韩美制药股价上涨9.8%，三星Epis控股股价飙升14.33%。

在韩国创业板（Kosdaq）上，LigaChem Biosciences 股价上涨 7.41%，Alteogen 股价上涨 3.68%。

韩元兑美元汇率下跌0.6韩元，收于1342.1韩元。

发布于2026年11月5日下午4:26（韩国标准时间）

周四，位于首尔韩亚银行总部的股票行情显示屏显示了韩国两大半导体巨头的股价走势。SK海力士股价暴跌9.46%，至126万韩元；三星电子股价下跌7.57%，收于20.15万韩元。（韩联社）

周四，韩国股市暴跌，原因是人们担心美国将收紧对人工智能 (AI) 和数据中心发展的监管，引发半导体股票全面抛售，此前民主党在中期选举中大获全胜。

据韩国交易所数据显示，韩国综合股价指数（KOSPI）开盘报5580.09点，较前一交易日收盘下跌1.82%。该指数全天保持下跌趋势，最终收于5383.80点，下跌5.28%。

此次下跌主要受三星电子和SK海力士这两家韩国半导体巨头股价暴跌所致，这两家公司合计约占韩国综合股价指数（KOSPI）市值的一半。它们过高的权重使得该指数极易受到市场对芯片行业情绪变化的影响。

SK海力士股价暴跌9.46%，至126万韩元；三星电子股价下跌7.57%，收于201500韩元。

韩国芯片股的疲软延续了隔夜美国相关股票的抛售势头。英伟达股价下跌3.17%，而芯片制造商美光科技和闪迪的股价分别下跌7%和7.91%，原因是市场担忧更严格的监管环境可能会减缓人工智能基础设施的扩张。

美国中期选举民主党取得历史性胜利，同时掌控了参众两院。这一结果引发了人们的担忧：民主党主导的国会可能会对人工智能的研发和投资实施更严格的监管，而对数据中心基础设施扩张的政治支持也可能变得不那么确定。

投资者尤其担心数据中心建设的延误可能促使大型云计算公司重新评估投资计划的时间安排。这反过来又可能影响韩国制造商供应的高带宽内存和其他先进芯片的需求前景。

民主党的胜利可能会加剧人工智能支出和韩国芯片制造商面临的压力

随着民主党重新掌控美国国会，首尔股市面临新的不确定性。

然而，选举结果也为其他行业创造了潜在的机遇，特别是可再生能源和制药行业。

受民主党将推进旨在降低医疗保健成本和支持清洁能源的政策预期影响，韩国制药商和生物技术公司的股价上涨。

在医疗保健方面，该党的政策议程包括努力保留医疗补助资金并扩大政府对医疗保险的援助，这可能会为品牌药的低成本替代品创造更有利的环境。

如果美国控制药品支出的努力促使生物类似药得到更广泛的采用，那么韩国生物类似药生产商可能会从中受益。生物类似药以更低的价格提供与原研生物药类似的疗效。

Celltrion股价较前一交易日上涨7.5%，韩美制药上涨9.8%，三星Epis控股股价飙升14.33%。

生物科技股在韩国创业板（Kosdaq）交易所也表现优异，其中 LigaChem Biosciences 上涨 7.41%，Alteogen 上涨 3.68%。

周二，在德克萨斯州奥斯汀，支持者们在为德克萨斯州民主党参议员候选人、州众议员詹姆斯·塔拉里科举行的中期选举之夜守夜派对上庆祝。法新社-韩联社

Kiwoom Securities 分析师韩智英表示：“人们担心新的数据中心项目可能会延误，这可能会拉大人工智能相关股票（如半导体和电力设备）与非人工智能行业（如二次电池和太阳能）之间的差距。”

不过，她预计对芯片制造商的影响有限，因为已在进行中的数据中心项目不太可能出现重大延误，现有供应合同和人工智能基础设施公司的盈利预测基本不会受到影响。她补充说，考虑到总统的否决权、民主党内部的意见分歧以及华盛顿维护其在人工智能领域领先地位的决心，全国范围内的限制措施难以实施。

在首尔外汇市场，韩元兑美元汇率下跌0.6韩元，收于1342.1韩元。