Well the CNBC contest started out with controversy and it appears it will end with controversy. Reuters has the story…

The cable network said on Wednesday that it is investigating whether entrants in its “CNBC Million Dollar Portfolio Challenge” contest engaged in illicit trading to boost their results.

“CNBC has been contacted by several contestants alleging unusual trading in violation of contest rules among some of the 20 finalists,” the cable news network said in a statement.

“Once these questions were raised, CNBC immediately launched a thorough investigation to determine who may have violated the rules,” it added.

The probe was looking at “unusual trading” and “potential irregularities,” CNBC said.

UPDATE: The New York Post’s Paul Tharp provides some additional background color…

But one red flag involved the fact that only 375,000 players joined the online contest, which ended May 25 - yet more than 1.5 million separate portfolios were created.

One trader opened as many as 803 portfolios under her name, said one chat-room user.

Others blasted CNBC for letting the game become so easily rigged before a winner could be announced July 9.

“I say we put together a massive joint class action asking for $10,000 for each person . . . and stick it to CNBC,” said one blogger.