Prosecutors on Friday asked the Tokyo District Court to send Yoshiaki Murakami to prison for three years, fine him 3 million yen and make him forfeit 1.1 billion yen to cover the estimated profit he made in 2004 and 2005 on alleged insider trading involving Nippon Broadcasting System Inc.

Prosecutors asked the court to give Murakami the biggest-ever financial penalty for insider trading, describing him as "lacking even the minimum of ethics" for using inside information about Livedoor Co.'s plan to buy shares in NBS to make a profit.

"The crimes were not committed based on information obtained by chance, but under conditions the accused created himself in order to make a huge profit," one prosecutor told the court.