The Securities and Exchange Commission has taken enforcement action against 23 companies in connection with statements made relating to COVID-19 and is warning investors to beware of fraud, illicit schemes and other misconduct during the pandemic.

The latest moves came Wednesday, when the SEC halted trading of Salt Lake City, Utah-based Predictive Technology Group Inc. PRED, -15.78% and New York-based SCWorx Corp. WORX, +2.81% over questions regarding the accuracy of public information about their plans to sell COVID-19 tests.

“The Enforcement Division is committing substantial resources to ensuring that our Main Street investors are not victims of fraud or illegal practices in these unprecedented market and economic conditions,” the SEC said in a March 23 statement.

Many small biotech companies and microcaps that trade over the counter are not obliged to make the same financial disclosures as bigger companies. But some have seen their stocks soar on hopes they will be able to cash in on the need for testing and treatments for the pandemic, which has infected 2.67 million people worldwide and caused 186,131 fatalities, according to data aggregated by Johns Hopkins University.

In February when the virus was beginning to hit the headlines in the U.S., the SEC warned of the possible emergence of fraudsters, who would use the news to lure investors into scams. The regulator highlighted the proliferation of internet promotions, often using social media, claiming products or services that could prevent, detect or cure the virus, and that would lead those companies’ stocks to rise dramatically as a result.

Just as happened at the height of the mania around cryptocurrency and later cannabis, COVID-19 promotions often appear in the guise of “research reports” while actually being pump-and-dump schemes, said the SEC.

“We urge investors to be wary of these promotions, and to be aware of the substantial potential for fraud at this time,’ said the statement.

Among the actions taken, on April 15, the SEC halted trading in the shares of Bravatek Solutions Inc. BVTK, , a Colorado-based company with operations in Austin, Texas, that claimed to be working with the Environmental Protection Agency to gain approval for a disinfectant that it said killed the virus.

On April 13, the SEC halted trading in the shares of Aarayit Corp. ARYC, +53.84% , a Nevada corporation with its main business operation in Sunnyvale, California for claiming it had an approved COVID-19 blood test.

That same day, the regulator halted trading of the shares of Applied BioSciences Corp. APPB, over claims made regarding the sale of COVID-19 home testing kits. A similar claim made on a cable new program by the chief executive of Florida-based Solei Systems Inc. SOLI, -0.08% led to that stock being halted on April 10. The SEC also halted the stock of Parallax Health Sciences Inc. PRLX, for claims relating to a rapid screening test and large quantities of diagnostic kits and personal protective equipment, all of which are greatly in demand.

Some of the companies affected have been the targets of short-selling reports alleging fraudulent claims relating to the virus, that address misdeeds conducted by executives at other companies.

Predictive Technology Group Inc. and SCWorx Corp., for example, have both been the subjects of reports by Hindenburg Research that alleged that certain executives had been embroiled in securities fraud suits in the past. Nathan Anderson, partner at Hindenburg, commended the SEC on Wednesday for its action.

Predictive did not respond to a request for comment. SCWorx directed MarketWatch to its previous press releases and SEC filings.

For a full list of the SEC’s enforcement actions relating to COVID-19:Click here

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