Bill Ackman's position in Visa is currently worth $774M. That's 5.36% of their entire equity portfolio (10th largest holding). Bill Ackman started to build up the position in Visa in Q3 2008 and continued to invest until Q4 2008. Since then they sold 4.93M shares. The stake costed the investor $34.5M, netting the investor a gain of 2145% so far.