The Dodd-Frank financial overhaul bill passed in July 2010 has a requirement that issuers of mortgage securities hold onto 5% of the risk of mortgages packaged into securities. Regulators were required to to write the rules for certain exempted loans called "qualified residential mortgages" for which the rules do not apply. Kenneth Rosen of the University of California, Berkeley, says the requirement aims at avoiding the catastrophic risk-taking epidemic that caused the financial crisis of 2008. Federal regulators have till December 2010 to write the new rules. But financial trade groups and firms are already pressing their views on what they would like to see exempted from this crucial 5% requirement.