Shares of the payments and bank technology company Fiserv (NASDAQ: FISV) traded nearly 6% higher, as of 1:17 p.m. ET. The Wall Street Journal reported earlier that activist investor Jana Partners has built a stake in the company and is lobbying for change that will lift the struggling stock. Big turnaround ahead The Wall Street Journal cited anonymous sources in its reporting, saying Jana supports the current CEO, Mike Lyons, who took the position last May. While Jana's position at Fiserv is unknown, the ...