The Supreme Court of the United States revived a class action case accusing ING Groep NV of illegally hiding the risks of mortgage-backed securities following the high court’s decision regarding pharmacy services firm Omnicare last week. 

Justices this morning threw out a November 2013 decision by the Second U.S. Circuit Court of Appeals in favor of the Dutch ING and a number of banking firms.

This means that Freidus et al v. ING Groep NV et al will be sent back to a lower court for consideration.

The lawsuit, initially filed in February 2009, claimed that ING concealed the risky nature of mortgage-backed securities. Investors say that ING violated a provision of the securities laws that prohibit false statements in statements filed with the U.S. Securities and Exchange Commission, thereby knowingly hiding the nature of the risk.

In the Omnicare case, the high court found that shareholders cannot sue public companies for issuing statements ahead of a public stock offering simply because they turn out to be untrue. 

It is the second part of the decision that bodes well for mortgage bond investors.

According to the Wall Street Journal, the Supreme Court ruled that a company can be held liable for securities fraud "if it omits facts from its registration documents that would raise serious questions about the validity of the opinions a company expresses to investors."

ING is a Dutch investment firm and insurer. It received a bailout from the Netherlands and is liquidating all non-core, non-insurance assets as part of the conservatorship. As part of those bailout terms, the financial firm is required to reduce its foreign, legacy investments.

ING only finally divested itself of all of its U.S. ventures earlier this month.