It looks like investors in the old General Motors are finally starting to get it.

Maybe they just had to be hit over the head a few times before realizing that shares in old GM are worthless.

It took a very firm warning from securities regulators and a change of the company's stock symbol from GMGMQ to MTLQQ to lessen interest the company's shares diminished Wednesday, the first day of trading under the new symbol.

Shares in the company, traded over the counter and now called

Motors Liquidation


, fell 52% on Wednesday on volume of 102.3 million.

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On Friday, as new GM emerged from bankruptcy, misguided traders bid up the price of old GM 37%.

"Despite several company disclosures warning investors that the old GM stock would likely have no value, it continued to trade at significant volumes and at prices far in excess of its likely value," GM spokeswoman Renee Rashid-Merem said Wednesday. "The new symbol, MTLQQ, should help to avoid confusion in the marketplace with new GM, which today is privately held and is not publicly traded whatsoever."

The Financial Industry Regulatory Authority, or Finra, noted that as recently as last week, "Newsletters and other promoters have touted the purchase of the stock." The agency said some investors may have failed to understand that new GM and old GM are separate and distinct companies.

Additionally, "investors are often confused by the fact that, despite the likelihood that the common stock of a bankrupt company will be cancelled, the company's securities may continue to trade after the company has filed for bankruptcy protection and before it emerges as a newly reorganized company," Finra said. "This confusion may be aggravated by the lengthy bankruptcy process -- which may take months, if not years."


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is the only U.S. automaker that is publicly traded. Shares of New GM are expected to become available to the public in 2010.

Ford shares closed Wednesday at $6.05, up 3.6%.