The chief executive and co-founder of leading antivirus firm Trend Micro has been ordered to pay a fine by US financial watchdogs. 

The US Securities and Exchange Commission (SEC) will now drop an ongoing investigation into Eva Chen, following allegations of insider trading and financial disclosure irregularities.

Trend Micro said in a statement that Chen "neither admitted nor denied the allegations, and agreed to pay the SEC a civil penalty and not to violate the securities laws".

The investigation related to allegations of suspicious trading of shares in the major Chinese internet portal, Sina.com.

Chen's husband, Daniel Chiang, was a co-chairman of Sina during the late 1990s, prior to which he was president of Trend Micro.

In addition to the allegations of insider trading, Trend Micro announced last year that SEC staff had also "inquired into whether Ms. Chen under-reported her holdings in Trend Micro shares".

Chen joined Trend Micro when the company was founded in 1988 in Taiwan by her brother-in-law, Steve Chang. She became chief executive in 2004.

Trend Micro posted consolidated net sales of $180m for the third quarter of 2006, a year-on-year increase of 17 per cent, according to the firm. Net profit was $32.85m, down 13 per cent on the same quarter the previous year.

"Much of the company's worldwide growth was buoyed by strong sales in small and medium business and consumer solutions which experienced a 19 per cent and 20 per cent increase respectively year over year," the company announced.