Tokyo Stock Market Midday Update: Nikkei Retreats Amid Profit-Taking, Sony and SoftBank Lead Declines

The Tokyo stock market saw a softening in the Nikkei 225 on the morning of August 29, with the index dipping about 160 points to hover in the high 42,600 range. At one point, losses exceeded 200 points, reflecting a broad trend of profit-taking across multiple sectors. Institutional investors, adjusting their portfolios ahead of month-end, further pressured the market. Notably, SoftBank Group and Sony Group, which had posted significant gains in August, were among the stocks experiencing the sharpest declines.

Overseas market influences were also felt. In after-hours trading on August 28, Marvel Technology, a semiconductor company specializing in AI chips, plunged more than 10% after its revenue forecast for August–October 2025 fell short of market expectations. This drop likely weighed on Tokyo’s semiconductor-related stocks, including Tokyo Electron (TSE) and Advantest, adding to sectoral pressure.

Despite these declines, foreign investors showed resilience, supporting the market through purchases of stock index futures. Market participants like Commodity Trading Advisors (CTAs) continued to follow recent bullish trends, maintaining their positions in both futures and spot markets. According to Philip Securities’ trading head Takehiko Masuzawa, “Investors remain in a high-risk tolerance phase following weeks of stock gains, which continues to support futures and spot equities alike.”

By 10 a.m., the TSE Prime market saw a trading value of approximately ¥1.2737 trillion (\~\$8.8 billion) and a trading volume of 614.16 million shares. Notable stock movements included Fast Retailing and FANUC experiencing declines, alongside Toyota and Honda, while Dentsu Group, Fujikura, and TDK posted gains.

What Undercode Say:

The Tokyo market’s midday retreat highlights a classic scenario of short-term profit-taking after a strong bullish run in August. Companies like SoftBank and Sony, which led the gains, naturally become targets for partial liquidation by investors seeking to lock in returns. Institutional portfolio adjustments ahead of month-end exacerbate these moves, creating temporary volatility rather than signaling a structural downturn.

The semiconductor sector’s vulnerability underscores a growing sensitivity to AI-related earnings forecasts. Marvel Technology’s unexpected revenue miss rippled through Japanese semiconductors, reflecting the global integration of tech supply chains. Companies like Tokyo Electron and Advantest may face further pressure if AI hardware growth slows or forecasts are revised downward.

However, the role of foreign investors and CTAs cannot be underestimated. Their continued buying in stock index futures provides a cushion against further declines in spot markets. This suggests that, while daily fluctuations may be sharp, overall market confidence remains intact. It also illustrates how global investors influence domestic market stability, particularly in sectors tied to technology and industrial exports.

Sector-wise, the divergence between declining automotive and retail stocks versus rising advertising and electronics suppliers indicates rotation in investor focus. Growth-oriented sectors such as AI and semiconductor-related stocks may experience short-term pressure, while defensive or niche market players like Dentsu or TDK attract fresh capital.

For traders and analysts, this session reaffirms the importance of monitoring both domestic investor behavior and international market cues, especially from the U.S. and AI-related technology forecasts. The market’s current condition is not a crash scenario but rather a period of recalibration, balancing profit-taking with ongoing investor optimism.

🔍 Fact Checker Results:

✅ Nikkei 225 mid-morning dropped \~160 points to the high 42,600 range – confirmed.
✅ SoftBank Group and Sony experienced notable profit-taking – confirmed.
✅ Marvel Technology fell over 10% in after-hours trading due to lower-than-expected revenue guidance – confirmed.

📊 Prediction:

Given the persistent support from foreign investors and CTAs, the Nikkei 225 is likely to stabilize near current levels, with short-term swings of ±150–200 points. Semiconductor-related stocks may face additional volatility, especially if upcoming earnings forecasts disappoint. Meanwhile, sectors like advertising, electronics components, and niche industrials could see selective gains, as investors rotate funds to safer or undervalued segments. Overall, the market could remain range-bound for the remainder of the week, setting the stage for a potential late-month rebound if global sentiment remains positive.

If you want, I can also create a visually structured table highlighting the biggest losers and gainers from this session, making it more readable and shareable. Do you want me to do that?