The Security and Exchange Commission suspended trading in four microcap companies touting development of Ebola-related treatments or services, citing a lack of publicly available information about their operations.
The companies—Bravo Enterprises, Immunotech Laboratories, Myriad Interactive Media and Wholehealth Products—were not able to be reached for comment.
"Questions have arisen concerning the accuracy and adequacy of publicly disseminated information, including information about the relationship between the company's business prospects and the current Ebola crisis," the SEC filing said.
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All four firms were traded on the over-the-counter market, which is typically where the majority of SEC suspensions occur, according to the Financial Industry Regulatory Authority.
The agency has the authority to suspend trading for up to 10 trading sessions.
The SEC also issued an investor alert about the potential for fraud and said investors should be aware of "con artists" who exploit pandemics in the news to lure investors.
As an example, the agency pointed to natural disasters such as Hurricane Katrina and Hurricane Sandy, which spawned a hosts of investment schemes for companies purportedly involved in cleanup efforts.
"We move quickly to protect investors when we see thinly traded stocks being promoted with questionable information that make them ripe for pump-and-dump schemes," Elisha Frank, Co-Chair of the SEC Enforcement Division's Microcap Fraud Task Force, said in a written statement.
"Fraudsters are constantly exploiting issues of public concern to tout a penny stock company supposedly in the business of addressing the latest crisis."