BENGALURU, July 9 (Reuters) - Indian ride-hailing firm Ola, backed by Japan’s SoftBank Group Corp, said on Friday private equity firms Temasek and Warburg Pincus are investing $500 million in the startup ahead of its planned initial public offering. (Reporting by Nallur Sethuraman in Bengaluru; Editing by Shounak Dasgupta) Our Standards: The Thomson Reuters Trust Principles.