Nikkei 225 Plunge Highlights Volatility in AI Stocks
The Nikkei 225 Stock Average rebounded after a sharp drop (plunge) on November 4, 2026, but still closed down 1.42%. The key message for investors from the move reported by Yonhap Infomax is not the size of the index decline, but that selling concentrated in AI and semiconductor-related stocks before spreading to trading houses and automakers.
The Nikkei 225 Stock Average is the benchmark index of the Tokyo stock market. The day’s price action can be characterized as a correction that extended beyond selected AI-related stocks into broader market risk aversion before partially reversing from the intraday low.
The Gap Between the 62,188.63 Closing Price and Intraday Rebound
According to Yonhap Infomax, the Nikkei 225 Stock Average closed at 62,188.63 on November 4, 2026, down 893.23 points from the previous session. The 1.42% decline left the closing price at its lowest level since July 30, 2026.
At the end of the morning session, the index stood at 60,835.36, down 2,246.50 points from the previous closing price. It fell as low as 60,030 in afternoon trading, its weakest level in about six months, before paring its losses. While the closing price indicates a down market, the intraday path reflected a clash between selling pressure and bargain buying near the lows.
Declines in Kioxia Holdings and Advantest
Kioxia Holdings suffered a 15% sharp drop (plunge) at one point during trading on November 4, 2026, while Advantest, described as a semiconductor materials, components and equipment company, fell as much as 10%. SoftBank Group and Tokyo Electron were also cited alongside Kioxia Holdings as Japanese AI and data center-related stocks.
These figures show that the price shock in related stocks was steeper than the index decline. The investment implication of this price action is that when policy uncertainty surrounding the AI industry comes into focus, the market may mark down stocks in the same category before distinguishing between the actual regulatory provisions and their company-specific effects.
How AI Selling Spread to Cyclical Stocks
Trading houses and automakers, which had remained resilient during the morning session, turned lower in the afternoon. Although the sharp drop (plunge) in AI and data center-related stocks was the most visible move, the underlying pattern was a broadening of selling into cyclical stocks. Interpreting the selloff solely as a problem affecting specific technology stocks would overlook the broader shift in market risk appetite.
Nikkei reported that the Japanese market’s intraday sharp drop (plunge) was an unexpected reaction because expectations of a Democratic advantage had already circulated ahead of the U.S. midterm elections. This indicates a gap between widely known expectations and the actual market response. The precise impact of the U.S. midterm elections on the index and individual stocks, as well as the details and implementation status of any U.S. Democratic regulations on the artificial intelligence industry, have not been confirmed.
Assessments from Minoru Kihara and IwaiCosmo Securities
Chief Cabinet Secretary Minoru Kihara said, “I will refrain from commenting on the government’s position, but the government will continue to monitor market developments with a heightened sense of vigilance.” The statement indicates that the government is watching market volatility; it does not imply any separate policy action or outcome.
An investment strategy analyst at IwaiCosmo Securities explained, “Japanese stocks have also tended in the past to face concentrated risk-averse selling following U.S. election results.” If this assessment is correct, investors should avoid concluding from the intraday sharp drop (plunge) alone that the value of the affected companies has changed. Subsequent price action will be needed to distinguish temporary selling from a sustained revaluation.
Three Sets of Signals for Korean Investors to Watch
- Nikkei 225 Stock Average: If the rebound from the intraday low continues, investors can consider a scenario in which short-term risk aversion eases. If the rebound falters, it would strengthen the interpretation that selling pressure remains after spreading to cyclical stocks.
- AI and data center-related stocks: Investors should watch whether Kioxia Holdings, SoftBank Group and Tokyo Electron continue moving in the same direction or begin following stock-specific paths. Continued weakness across the group would indicate a broader thematic revaluation, while divergence would signal a shift toward company-specific assessments.
- Semiconductor equipment trend: Investors should monitor whether Advantest reverses its intraday sharp drop (plunge). With the actual regulatory provisions and their implementation status still unknown, the price reaction does not demonstrate a change in the company’s earnings.
- Scope of selling: Investors should check whether the afternoon weakness in trading houses and automakers persists. A recovery in these industry sectors would support the view that the impact has narrowed again to AI and semiconductor-related stocks.
Diverging Scenarios Between the Plunge and Rebound
The favorable scenario would be for the Nikkei 225 Stock Average to maintain its intraday rebound while synchronized weakness in AI and data center-related stocks and cyclical stocks subsides. Under this scenario, the market would be moving closer to absorbing post-election risk aversion as a temporary price shock.
Downside risk would emerge if related stocks remain weak and selling continues to affect trading houses and automakers. What has been confirmed so far is the price sequence of a sharp drop (plunge), broadening losses and a rebound. The future direction of the index and related stocks remains unknown, and the next assessment will depend on the actual regulatory provisions and whether stock-specific price differentiation emerges.
This article was automatically summarized and analyzed from the original news report. View the original article (Yonhap Infomax)
