With an estimated $1.2 trillion under management it’s clear that hedge funds must have an effect on the financial markets. The question is: How? In one of the first studies to shed light on that subject researchers at Wharton and three other business schools find that hedge funds’ efforts to improve companies they hold big stakes in have spillover benefits for all shareholders: a quick 5% to 7% jump in stock prices. The gains measured as an ”abnormal return” on top of the broad market’s were nearly 11% when a hedge fund pushed for the targeted company to be sold.