The chief financial officer of Samuel Adams producer, Boston Beer Co, resigned late on Monday, the same day as he made a profit selling the brewer's shares, a regulatory filing showed.

Richard Lindsay, Boston Beer's treasurer and CFO, said in a statement that he would leave the company at the end of March "to pursue advanced educational goals and other professional opportunities."

Lindsay also exercised an option for 1,000 class A common shares at US$7.15625 each on Monday and then sold the shares at US$12.50 each, leaving him with direct ownership of 200 shares, according to a filing with the US Securities and Exchange Commission. On these figures it has been reported that Lindsay made a profit of more than US$5,300 on the shares on Monday. However, according to separate SEC filings, he also exercised options for 5,000 shares at US$7.15625 each last week and then sold the shares at higher prices.

Shares of Boston Beer fell more than 8% on Tuesday to US$11.56, their lowest level since November 2001.