Citadel Ready to Spar With Gensler’s SEC Over WhatsApp Probe

Citadel is preparing to push back against the Securities and Exchange Commission’s WhatsApp probe, taking a harder line than the almost two dozen banks that have paid hefty settlements over the past two years.

Ken Griffin’s hedge fund has told industry peers that it plans to battle the SEC if the regulator moves against Citadel, according to people familiar with the talks. And it’s willing to take the agency to court, said the people, who asked not to be identified discussing private conversations.

The Miami-based firm would be the first to fight the SEC over any allegations of ...