Softbank CEO Son says 'very supportive' of Alibaba's partnership HONG KONG/TOKYO (Reuters) - Softbank Corp CEO Masayoshi Son said on Friday the company fully supports a partnership system in Chinese e-commerce giant Alibaba Group Holding Ltd. The group of 28 partners in Alibaba include the company's founder Jack Ma, some of Alibaba's senior managers and other insiders. Alibaba, which is preparing for an initial public offering valued at up to $15 billion, is looking to keep top management decisions within the partner group by giving it the right to nominate a majority of board members in the company. "Alibaba has built a phenomenal business and created tremendous value for its shareholders over the years," Son said in a statement. "We are therefore very supportive of the Alibaba partnership structure," he added. Reporting by Elzio Barreto in Hong Kong and Mari Saito in Tokyo; Editing by Paul Tait