Siegel heads the Tokyo office of law firm Morrison & Foerster and has worked on some of SoftBank's biggest deals. Proxy adviser Glass Lewis urged https://www.reuters.com/article/softbank-group-corporate-governance-idCNL3N2NQ095 shareholders to oppose his election due to his professional ties to the conglomerate.

Shareholders voted 69.77% in favour of Siegel's election. Nominees need a majority of votes to join the board.

By contrast shareholders voted 99.85% in favour of the SoftBank's other new independent director, gaming executive Keiko Erikawa. Founder and CEO Masayoshi Son received 97.92%.

The vote comes amid increasing displays of investor displeasure in Japan, which is known for its conservative corporate culture, with the ousting of Toshiba's chairman on Friday seen as a watershed moment.

Criticism has frequently focused on the makeup of SoftBank's board, which is said to lack voices that can stand up to Son. The group reported record earnings in the year ended March, burnishing the billionaire's investing credentials.

Son called on shareholders on Wednesday to take a long-term view on the company, which he described as a "capital provider for the information revolution."

(Reporting by Sam Nussey; Editing by Edmund Blair and Kim Coghill)

By Sam Nussey