The Nikkei 225 index fell more than 1,600 points [1] during morning trading as investors sold AI and semiconductor-related stocks.

This volatility highlights the heavy influence of a few high-growth tech sectors on Japan's primary benchmark. While the headline index plummeted, the broader market showed resilience, suggesting the sell-off was concentrated rather than a systemic collapse.

The Nikkei 225 ended its morning session 809 points lower at 66,661 [2]. However, other reports indicate the index traded in the 69,000-yen range [5] later in the session. The sharp decline was triggered by profit-taking sell orders specifically targeting AI and semiconductor stocks [1].

Despite the drop in the Nikkei, the TOPIX index closed in positive territory [3]. This divergence is further evidenced by the fact that approximately 80% of all listed stocks on the Tokyo Stock Exchange rose [4].

Market analysts said the downward pressure on the Nikkei was not solely due to tech profit-taking. Broader sentiment was also weighed down by rising oil prices and retreating expectations for U.S. rate cuts [6]. These macroeconomic factors created a challenging environment for the heavy-weight stocks that dominate the Nikkei's price-weighted calculation.

The contrast between the Nikkei and the TOPIX suggests that investors are rotating capital out of overpriced tech leaders and into a wider array of domestic companies. This shift indicates a broadening of the rally across the Japanese equity market, even as the most visible index faces a correction.

The Nikkei 225 index fell more than 1,600 points during morning trading.

The stark difference between the Nikkei 225's crash and the TOPIX's gain reveals a market imbalance. Because the Nikkei is price-weighted, a drop in high-priced semiconductor giants can distort the perceived health of the Japanese economy. The fact that most listed stocks rose suggests that the underlying market breadth is strong, despite the volatility in the AI sector.