HedgeCo.Net — Hedge fund traders positioned this week for the largest rebalancing in the history of Japan’s Topix benchmark, a reshuffle of more than 700 stocks expected to generate about $60 billion of passive trading at Thursday’s close, Bloomberg reported.
The flows are expected to split roughly evenly, with about $31 billion each of buying and selling by exchange-traded funds and other index trackers, ahead of changes that take effect on Friday, October 30. The overhaul includes additions, deletions and free-float weight adjustments and will be implemented in eight quarterly phases through mid-2028, part of Japan Exchange Group’s multiyear effort to make the index more investable.
Daiwa Securities estimates that index-tracking funds will need to reallocate about 3.1% of their portfolios, compared with 1.8% in the previous restructuring completed in January 2025, according to Hedgeweek. The defined inclusion criteria have allowed index arbitrage and event-driven funds to build long and short positions in advance.
The trade has not been one-way. Hedgeweek reported that chipmaker Kioxia has fallen nearly 30% since the changes were announced on October 7, despite being set for a higher index weighting. Célia Fseil, head of equity market neutral at Candriam, warned that concentrated activity in the closing auction creates opportunity for arbitrage strategies but also raises execution risk.
The rebalance comes as hedge fund interest in Japanese equities stays elevated, supported by governance reforms and a Topix that has gained about 17% this year. Because the rebalance is phased through mid-2028, index-event specialists could see a recurring quarterly opportunity rather than a single trade.