Kremlin Insider in U.S. Hands May Have Secrets of 2016 Hack (1)

In the days before Christmas, U.S. officials in Boston unveiled insider trading charges against a Russian tech tycoon they had been pursuing for months. They accused Vladislav Klyushin, who’d been extraditedfrom Switzerland on Dec. 18, of illegally making tens of millions of dollars trading on hacked corporate-earnings information.

Yet as authorities laid out their securities fraud case, a striking portrait of the detainee emerged: Klyushin was not only an accused insider trader, but a Kremlin insider. He ran an information technology company that works with the Russian government’s top echelons. Just 18 months earlier, Klyushin received a medal ...