A former director of sales for U.S. chipmaker Qualcomm Inc (QCOM.O) pleaded guilty in San Diego on Thursday to insider trading, officials said.

Derek Cohen, 52, admitted that he netted about $200,000 from a series of stock and options trades made after learning that the company planned to buy Atheros Communications in 2011, a statement from the U.S. Attorney's Office in San Diego said.

As knowledge of pending Atheros acquisition spread within Qualcomm, Cohen spent about $430,000 on stock and call options. When the deal was reported in the media, the stock's value leapt higher, the statement said.

Cohen, who had earlier pleaded not guilty, was the fifth person to admit guilt in connection with the deal, according to court records.

Former sales director Robert Herman pleaded guilty in July to making about $30,000 from trading the stock before and after the acquisition, while Michael Fleischli pleaded guilty to netting about $3,000, prosecutors said.

Herman was sentenced to three years probation, a $50,000 fine and community service, while Fleischli was placed on three years of probation-like supervision under a deferred prosecution agreement, the statement said.

Jing Wang, a former executive vice president and president of Qualcomm's global operations, pleaded guilty to insider trading and money laundering in July, admitting that he made $240,000 from trading Atheros stock through a secret brokerage account. His stockbroker, former Merrill Lynch vice president Gary Yin, pleaded guilty to money laundering, officials said.

Sentencing hearings for Wang and Yin have yet to be scheduled, the statement said.

Cohen, who has agreed to forfeit the $200,000 he gained to the U.S. government, faces maximum penalties of 20 years in prison and fines up to $5 million. Sentencing is scheduled for May 22.