The

Securities and Exchange Commission

has issued subpoenas to some online message posters as part of an investigation into the trading practices of a high-profile online stock picker known as "TokyoMex."

The stock picker, Yun Soo Oh Park, who also goes by the names Joe Park and Tokyo Joe, confirmed that he is at the eye of a wide-ranging inquiry by regulators into his trading practices and disclosure methods.

"I welcome this challenge. I have nothing to hide," Park says, adding that last week he received SEC requests for letters, emails and other information concerning stocks he has recommended over the Internet. Park says he has hired lawyers in Chicago (the SEC's Midwest office issued the subpoenas) and in New York, where he lives.

An SEC spokesman would neither confirm nor deny the existence of any investigation.

Copies of a subpoena obtained by

TheStreet.com

instruct the recipient to appear before the SEC by March 19 to testify in the "matter of Yun Soo Oh Park, an investigation pursuant to a formal order issued" by the SEC. The recipient also was requested to bring "books, papers, documents and other records" concerning Park. A descriptive memo to the subpoena also cites Park's involvement in his Web site,

Tokyo Joe's Societe Anonyme

. The site is an online community of message board posters and traders who pay a $100 membership fee to gain access to Park's stock picks.

Park, a Korean native, former lawyer and New York City restaurateur, quickly made a name for himself on Internet message boards and Web sites as a successful stock picker. On Tokyo Joe's Societe Anonyme, he cites several media outlets that profiled him, including

TheStreet.com

and

The Wall Street Journal

.

Park attributes the SEC investigation in part to his high profile. "I could have kept my mouth shut," he says. Park also blames his enemies, including some who have been subpoenaed, for complaining to the SEC and sparking the investigation.

TokyoMex, who frequents a popular message thread called "Tokyo Joe's Cafe" on

Silicon Investor

, in 1995 began to amass a loyal following on message board sites. The three threads attached to Park's name on Silicon Investor total more than 100,000 posts.

From a look at the discussions on the threads and his Web site, TokyoMex and his followers seem to favor the penny-stock world, but Park also has played in big names like

Iomega

(IOM)

,

Polo Ralph Lauren

(RL) - Get Report

and

CMGI

(CMGI)

, according to published reports and his own Web site.

He has received acclaim from fellow investors who were able to make money alongside him by following his stock picks. He also has received disdain from online opponents who claimed he was selling into the run-ups in stock prices that his recommendations would often cause, leaving his followers with the stock after he moved on.

"They say I'm a pump-and-dump!" Park says. "Who isn't a pump-and-dump?"

Word of the subpoenas was leaking into the online community this week and was quickly disseminated by Park's detractors. "I've been reading some buzz that ... 'TokyoMex' is now being investigated by the SEC," wrote an SI poster called Bill Wexler on Monday. "Can anyone confirm this and significantly brighten my day?"

Park says he is waiting to hear back from the SEC, but has told his 920 members of the Societe Anonyme group, urging them to cooperate truthfully if they are questioned by regulators.