Whenever misleading information is being widely distributed about a firm whose securities are traded, the SEC takes such actions, an agency representative said.

"All we can say is that we suspend trading any time we think misinformation about specific securities is being reported," said Helene Glotzer, an SEC spokeswoman. "We're not making a statement that these companies themselves were behind the misstatements, but if the information is out there we feel it is important to let the investing public know; we'll continue our investigation, and if it is appropriate to take action against any of the companies, that is what we will do."

The suspensions are part of an SEC initiative known as Operation Spamalot, which was launched specifically to shield investors from spam e-mail "hyping" small company stocks.

SEC officials said that anyone who has received such e-mail will recognize the names of the companies who were suspended, as they are among the most frequently cited businesses in securities-related spam campaigns. The messages typically advertise some new product or impending deal that will increase the value of the companies and encourage investors to buy their low-priced securities, which are usually penny stocks.

For instance, among the companies whose shares were suspended is Apparel Manufacturing Associates, a Bloomfield, Conn.-based firm that markets itself as a management and development company focused on the fashion arena.