The US Securities and Exchange Commission (SEC) has filed insider trading charges against web pioneer Mark Cuban.
According to the SEC, Cuban illegally dumped shares in Mamma.com in 2004 after learning that the stock would be sold at a discounted price.
The SEC claims that Cuban then used the information to dump his shares before the transaction and avoided some $750,000 in losses.
"Mamma.com entrusted Mr. Cuban with non-public information after he promised to keep the information confidential," said Scott Friestad, deputy director of enforcement for the SEC.
"Less than four hours later, Mr. Cuban betrayed that trust by placing an order to sell all of his shares. It is fundamentally unfair for someone to use access to non-public information to improperly gain an edge on the market."
Cuban first came into prominence as the founder of Broadcast.com, which was acquired by Yahoo in 1999 for some $5.9bn worth of stock. Since then, he has remained in the spotlight as the founder of the HDnet television network and owner of the Dallas Mavericks basketball team.
In a written statement, Cuban vowed to fight the charges. "I am disappointed that the Commission chose to bring this case based upon its enforcement staff's win-at-any-cost ambitions," he wrote.
"The staff's process was result-oriented, facts be damned. The government's claims are false and they will be proven to be so."
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