TOKYO (Reuters) - Shareholder support for the reappointment of SoftBank Group ( SFTBF ) Chief Executive Masayoshi Son has fallen to 79.22% from 95.93% a year ago after proxy advisor Institutional Shareholder Services (ISS) recommended against his reappointment, a stock market filing showed on Tuesday.

ISS opposed Son's reappointment because the tech investment group had posted an average return on equity of less than 5% over the past five years, SoftBank said in a press release earlier in June.

Among Softbank's other directors, shareholder support for external director Kenneth Siegel remained low at 68.46%, compared with 66.9% last year. Siegel is managing partner of law firm Morrison Foerster in Tokyo and has been involved in some of SoftBank's highest-profile deals.