While the funds' exact objection was not spelled out, one reason could be perks. Facebook Chief Executive Zuckerberg was paid $1.99 million in 2012, according to its proxy filing, much less than other executives, like Chief Operating Officer Sheryl Sandberg, who received $26.2 million. Yet ISS, the influential proxy adviser to institutional shareholders, recommended votes "against" the compensation. It questioned practices such as stock awards and the $1.2 million spent on Zuckerberg's personal use of aircraft in 2012. Although shareholders backed Facebook's executive pay by a wide margin, the ballots cast by Fidelity—Facebook's largest outside shareholder and a longtime investor—show how dynamics have changed for Facebook now that it is a publicly traded firm, said Edward Hauder, a senior adviser at Exequity, a Chicago-based executive compensation consulting firm.