The Securities and Exchange Commission is looking into the trading of worthless shares of Motors Liquidation (MTLQQ), sources say.

Motors Liquidation is the new name for the former General Motors, the one that became a repository for the assets and liabilities that remain to be liquidated in bankruptcy court. It has no relationship with new GM, which emerged from bankruptcy on July 10.

The Financial Industry Regulatory Authority, the SEC and GM have issued warnings about the worthless shares, but some traders continue to buy and sell them.

Now "Finra and the SEC are trying to hunt down the people who are fluffing the company," said a source, involved in penny stock trading, who asked that his name not be used.

An SEC spokesman declined to comment. Finra has said it is reviewing the trades.

"Bearing in mind that we only have regulatory jurisdiction over securities firms and the individuals associated with them, we would definitely look at the trading associated with these shares, as with any instance where there is unusually high volume or unusual activity in a stock, and especially one with circumstances like these," said spokeswoman Nancy Condon. "We'll be looking at who was buying, who was selling and what the rationale was."

The SEC enforces securities laws including those that apply to providing false information.

Shares in Motos Liquidation have had an off week, losing about 10% of their value. Trading under the Motors Liquidation name and symbol began on July 13 at $1.15 a share. The shares have since fallen about 60%. On Friday afternoon, shares were trading down 5% at 44 cents.

Ford ( F), the only publicly traded America automaker, was trading down 18 cents to $6.80 a share Friday.

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