Regulators want to ease a rule that would require banks to share some risk in the complicated mortgage investments that helped cause the financial crisis.
The broader requirements would still have banks hold at least 5 percent of the securities on their books.
But banks now could exempt mortgages issued to borrowers who have debt that doesn't exceed 43 percent of their annual income. Regulators had proposed exempting mortgages in which buyers put down 20 percent. But banks complained that would exclude too many buyers with solid finances.
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The broadening of the exemption is the latest sign of banks' influence over the rule-making process, which began after Congress passed the sweeping financial overhaul law in July 2010.
Banks applauded the change.