Key facts
- Japan's TOPIX index is likely to fall below 1,000 constituents as early as 2026.
- The surge in AI-related stocks, led by Kioxia Holdings, is a primary driver for the exclusion of smaller companies.
- The Tokyo Stock Exchange's ongoing market reforms are also contributing to the index's shrinking size.
- Companies must improve market valuations and capital efficiency to avoid being dropped from the TOPIX.
- The TOPIX aims to become a more concentrated and globally competitive benchmark.
Japan's broad Topix index is on track to significantly reduce its number of components, with projections suggesting it could fall below 1,000 constituents as early as 2026. This contraction is driven by the soaring market capitalizations of artificial intelligence (AI)-related companies, such as memory chip maker Kioxia Holdings, which are pushing out smaller and mid-cap stocks.
The Tokyo Stock Exchange has been implementing market reforms since October 2022, progressively removing stocks with a free-float market capitalization below ¥10 billion (approximately $61.6 million). However, the current accelerated decline in constituents is largely due to the rapid ascent of AI-related stocks, which has elevated the proportion of top-tier names within the TOPIX's total market capitalization.
Market participants suggest this dynamic will compel companies to enhance their corporate value to remain in the index. To stay included, firms must not only meet market capitalization thresholds but also maintain their relative presence in the broader market. The TOPIX's restructuring program aims to create a more concentrated and globally competitive benchmark, potentially halving its constituents by 2028.
On July 13, the Nikkei 225 fell 1,315.00 points to 67,242.73, and the TOPIX declined 28.59 points to 4,007.49. This downturn was primarily driven by profit-taking and selling pressure against AI-related stocks that had rallied previously. Investor sentiment is also being weighed down by uncertainty surrounding the Middle East situation and a lack of fresh buying catalysts. Despite this, the concentration of funds into select AI-related names is recognized as a structural trend, making the consolidation of TOPIX constituents an unavoidable trajectory.