Two of the four co-heads of securities trading at Goldman Sachs have decided to retire according to internal memos. David Heller and Edward Eisler have been with Goldman for 22 and 18 years, respectively. Heller spent more than 22 years at the firm working mainly in equities and equity derivatives and Eisler joined the bank 18 years ago and planted himself in trading interest rate products, currencies and commodities. Isabelle Ealet, global head of commodities, will join the two remaining exec
