Nikkei to lower Advantest's weight in Nikkei 225

AnnouncementsIndex coefficient to be cut in October after stock tops 10% limitNikkei to lower Advantest's weight in Nikkei 225 from October as stock's index share exceeds 10% cap rule.July 31, 2026 19:10 JSTTOKYO -- Nikkei will reduce the weighting of Advantest in the Nikkei 225 from Oct. 1, applying a cap intended to prevent any single constituent from becoming overly dominant.Based on the shares' July 31 closing price, the reference date for this autumn's periodic review, Advantest accounted for 12.2% of the index. This was above the 10% level that triggers the cap rule introduced in 2022.The Nikkei 225 is calculated using constituent share prices, multiplied by a price adjustment factor, which reflects past capital changes. Nikkei currently applies a factor of 7.2 and will reduce it to