Citadel just poached Two Sigma's data chief for its tech team — and it's the latest sign of how aggressively the $30 billion firm is pursuing top talent from Wall Street and Silicon Valley

· Citadel is adding Two Sigma's Andrew Janian, the $60 billion quant fund's former chief information officer and data chief, to its tech team.
· Ken Griffin's fund has poached several big names from Wall Street and Silicon Valley for its tech team in the past couple of years, including former Goldman Sachs partner Umesh...