The U.S. Securities and Exchange Commission (SEC), whileexpanding disclosure requirements for one set of asset-backedsecurities, has stepped back from a plan to shed more light on amajor part of the market.

On Wednesday, the five SEC commissioners unanimously approved arule to offer investors more details on bonds backed by assets suchas mortgages and car financing, including specific data onindividual loans, and new practices such as a cooling-off period toreview documents before certain bond sales.

Dropped from the rules: a requirement that issuers of privatesecurities be ready to furnish to buyers the same type ofinformation that's available for publicly registered debt. The SECsaid in a Federal Register posting proposing the rule in 2010 thatsuch a step would bring “transparency to formerly opaque”markets.