Beginning Oct. 1, sellers would be required to deliver a loan closing checklist of required documents. Consequences could range up to being forced to repurchase the loan. The recommendations were made by a joint task force of the MBA as well as the Commercial Mortgage Securities Administration.

"It puts into place a lot of things that should've been there before," says Daniel J. Hartnett, a partner with Chicago-based McDermott, Will & Emery. "It should make mortgage-backed securities better investments."

The task force spent eight months on its report and recommendations after investors, rating agencies, attorneys and lenders began noticing problems with missing loan documents. "In general, the trend was headed to a marked increase in litigation," says Pamela J. Dent, vice president of Moody's Investor Service.