A former quantitative analyst for a global asset manager was charged with securities and wire fraud for allegedly using nonpublic information to commit insider trading that netted him more than $8.5 million in profit, according to a complaint unsealed Thursday in federal court.

The analyst, Sergei Polevikov, who worked at OppenheimerFunds Inc., is accused of operating a front-running scheme in which he would use his wife’s personal brokerage account to buy or sell stock in advance of large pending purchase or sale orders by...

A former quantitative analyst for a global asset manager was charged with securities and wire fraud for allegedly using nonpublic information to commit insider trading that netted him more than $8.5 million in profit, according to a complaint unsealed Thursday in federal court.

The analyst, Sergei Polevikov, who worked at OppenheimerFunds Inc., is accused of operating a front-running scheme in which he would use his wife’s personal brokerage account to buy or sell stock in advance of large pending purchase or sale orders by his employer on behalf of its clients.

The alleged scheme took advantage of small price movements that generally happened during and following the firm’s purchases, according to the U.S. attorney’s office for the Southern District of Manhattan.

Mr. Polevikov, 48 years old of Port Washington, N.Y., was also charged with investment company fraud. He was expected to be arraigned Thursday afternoon. A lawyer for Mr. Polevikov couldn’t immediately be reached.

A spokeswoman for Invesco Ltd., which acquired OppenheimerFunds in 2019, didn’t immediately respond to a request for comment. Mr. Polevikov left the firm a few months after Invesco’s acquisition, according to the complaint and his LinkedIn profile.

Mr. Polevikov faces up to 20 years in prison on the securities and wire fraud charges, according to prosecutors. The Securities and Exchange Commission on Thursday also filed a lawsuit against Mr. Polevikov and his wife, seeking the return of his alleged illicit profits and civil penalties.

As an analyst, Mr. Polevikov had access to real-time information of pending trades in the fund’s internal system, according to prosecutors.

In trading on Jan. 22, 2018, he scored $96,358 in profits after using his wife’s account to buy and sell 400,000 shares of stock in Brazilian banking giant Itau Unibanco Holding SA, according to the complaint. Shortly after he purchased the stock, the complaint says, the fund bought nearly 8 million shares of Itau Unibanco, causing the share price to increase slightly. Mr. Polevikov sold his shares during the price fluctuation, according to the complaint.

The personal account of Mr. Polevikov’s wife shows about 2,800 instances of trading that followed a similar pattern, federal investigators said.

Mr. Polevikov carried out the alleged scheme between 2014 and 2019. During those years, he signed documents affirming he abided by his employer’s code-of-ethics policy and restrictions on personal trading by workers, which federal regulators require. Mr. Polevikov didn’t disclose his wife’s account to his employer, despite disclosing other personal accounts to his employer, prosecutors said.