Social Capital heralds new model for unicorn IPOs

‘Blank cheque’ company starts trading and looks for a tech giant to bring to market

Social Capital Hedosophia Holdings Corp. CEO, Founder and Chairman Chamath Palihapitiya, left, is applauded by New York Stock Exchange president Tom Farley as he rings a ceremonial bell when his company’s stock begins trading on the floor of the New York Stock Exchange, Thursday, Sept. 14, 2017 — AP Photo/Richard Drew

By Nicole Bullock in New York and Tom Braithwaite in San Francisco

A former Facebook executive and other Silicon Valley entrepreneurs want to rewrite the playbook for tech IPOs, listing a company on Thursday with the…