PORTLAND – A retired Fairchild Semiconductor executive blames the former Fleet Bank’s Private Client Group for the loss of a fortune once valued at more than $12 million in stock. The bank contends its financial advice was repeatedly ignored.

Darrell Mayeux made his fortune when Fairchild went public in 1999 while he served as vice president of sales and marketing. He received 667,000 shares of the company’s stock.

Three years later, it was gone.

The case, which is being heard this week in Cumberland County Superior Court, demonstrates how fast a fortune can be won and lost.

Fleet Bank suggested that Mayeux take out a $4 million line of credit and use his Fairchild stock as collateral; when the stock value dropped, his line of credit went out of balance and Fleet began selling off his stock, said his lawyer, Jonathan Piper.

“This is a case about a couple who entrusted their net worth to Fleet Bank, and three years later they had nothing,” Piper told jurors Monday.

Jerry Crouter, an attorney for Bank of America, which acquired Fleet, said Mayeux was repeatedly given advice that he didn’t take.

“This is a case about a man, Darrell Mayeux, who refused time and time again to follow the investment advice provided by the bank,” said Crouter. “It is a case about a man who made poor financial decisions about his stock.”

Piper said Mayeux was courted by Fleet’s Private Client Group soon after he was made wealthy by Fairchild’s initial public stock offering. The group caters to clients that have more than $1 million in assets.

He was invited to participate in a golf tournament, where he met the bank president, and later was given multiple presentations on the bank group’s services.

In 2000, Mayeux and his wife became clients of the Private Client Group and the line of credit was opened to make other investments to diversify his holdings because it was feared that selling off the Fairchild stock would have sent the wrong message, Piper said.

A year later, Mayeux retired from his job, but Fleet never changed its strategy, he said. Because Mayeux was no longer a Fairchild employee, he could have paid off the line of credit and followed a plan of diversification, Piper said, but no one suggested that.

Crouter said the diversification strategy failed for two reasons: Mayeux refused to sell his Fairchild stock, and he used the line of credit to invest in businesses and property instead of stocks and bonds for retirement.

Crouter said the Fleet Bank advisers told him “over and over” again to sell his Fairchild stock, but he always thought the price was too low. “He was waiting for the perfect price, but it was a perfect price that never came,” Crouter said.