NEW YORK—A former Wall Street quantitative analyst was charged on Thursday with insider trading for making nearly 2,900 trades after learning his employer would soon make the same trades for clients, known as front-running. The U.S. Department of Justice said Sergei Polevikov, 48, of Port Washington, New York, generated more than $8.5 million of illegal profit from trades he conducted from January 2014 to October 2019 through his wife’s brokerage account. Polevikov worked for OppenheimerFunds during the alleged front-running, according to a public records search. Prosecutors said his trades were designed to take advantage of small stock price movements he expected to occur that day once his employer filled large client orders. In a related civil complaint, the U.S. Securities and Exchange Commission said 2,858 of Polevikov’s 2,874 overlapping trades were in the same direction as his employer’s. Polevikov was charged with securities fraud, wire fraud and investment company fraud. …