Elliott Management buying up a sizable stake in Sumitomo is the latest in a string of Japanese deals for the firm, and reflects the growing influence of activist investors in the country.

Elliott has built a "large” holding in Sumitomo after investing "several tens of billions of yen” in the trading house backed by Warren Buffett. Founded by billionaire Paul Singer, Elliott also recently invested in developer Mitsui Fudosan, after previously targeting Toshiba, SoftBank Group and Dai Nippon Printing.

Activist investor campaigns are becoming more commonplace as the government and institutions such as the Tokyo Stock Exchange encourage companies to better manage balance sheets and boost shareholder returns.