By Shota Enokida

Yomiuri Shimbun Staff Writer

Sumitomo Mitsui Banking Corp. $(SMBC)$ and Toshiba Corp. have jointly formulated new stock indices utilizing quantum-inspired optimization technology.

One index tracks Japanese equities, while the other focuses on the U.S. market. The indices are made up of low-correlation stocks to mitigate risks associated with sudden changes in market conditions.

The two Japanese companies had never developed a stock index before.

The indices draw from a pool of 500 stocks listed on Japanese exchanges and 900 stocks on U.S. exchanges, and only stocks that have a low correlation to each other will be selected, while maximizing the number of constituent stocks.

The Japanese index will comprise about 60 stocks, while the U.S. index will be made up of about 90 stocks, according to SMBC and Toshiba. Mid-cap stocks will serve as the main constituents, and stocks that have been less volatile will be given a larger weight.

The new indices utilize a quantum-inspired optimization machine developed by Toshiba. It runs complex calculations to identify the optimal combination from a large pool of investment candidates -- a task that is difficult for conventional machines to perform. The portfolio of the new indices will be reviewed quarterly and will consist of at least 50 stocks.

"As Japan aims to bolster economic growth through asset management, we hope that the new stock indices will become a new, practical option for investors as part of our efforts to provide customer-centric financial products," said Arihiro Nagata, an SMBC senior managing executive officer.

----

This article is from The Yomiuri Shimbun. Neither Dow Jones Newswires, MarketWatch, Barron's nor The Wall Street Journal were involved in the creation of this content.

YDN-M0000203703-1

(END) Dow Jones Newswires

May 22, 2026 00:17 ET (04:17 GMT)

Copyright (c) 2026 The Yomiuri Shimbun