By Joe Light 

Investors who take over delinquent mortgages backed by Fannie Mae and Freddie Mac must try harder to reach agreements that let borrowers keep their homes before kicking them out, according to a new set of rules released Monday. The rules could limit foreclosures but also could cost taxpayers money.

The rules from the Federal Housing Finance Agency require investors to consider extending loan terms, forbearing or forgiving mortgage principal, or pursuing a short sale before foreclosure. When an investor does foreclose, for the first 20 days after the property is marketed, the investor can consider selling the property only to nonprofit groups or to people who intend to live in the house, rather than to other investors.

Fannie and Freddie don't make mortgages but buy them from lenders, wrap them into securities and guarantee to make investors whole if the mortgages default. When a default occurs, Fannie and Freddie try to mitigate their losses through getting a borrower to pay again or, eventually, through foreclosing upon the property.

Because such a process can take years and is expensive, both companies have lately considered selling the nonperforming loans to investors who would go through the process themselves. Loan buyers also have the flexibility to take drastic steps to keep homeowners in place, such as by cutting mortgage principal balances, which Fannie and Freddie are largely prohibited from doing. The companies are taking their cue in part from the U.S. Department of Housing and Urban Development, which has held auctions of nonperforming loans backed by the Federal Housing Administration for several years. Nonprofits have criticized some of those auctions.

The rules represent a nod to housing advocates who have long complained that some investors have treated homeowners roughly after buying loans formerly owned by the government. Some advocates had asked for the rules in response to what they said were anecdotal reports of ill treatment from some investors who bought the homes.

However, some investors say that they generally follow the practices outlined by the regulator already, and that to the extent the rules make them go through extra steps, it could result in lower prices for the loans, and steeper taxpayer losses.

The FHFA's rules essentially seek to ensure that investors who buy the loans make several attempts to keep borrowers in their homes before foreclosing.

"These guidelines are a great step toward ensuring that the auctions are more responsible and have the potential to benefit homeowners and neighborhoods," said Sarah Edelman, a senior policy analyst at the left-leaning Center for American Progress.

"FHFA expects that with these enhanced requirements, [nonperforming loan] sales by Freddie Mac and Fannie Mae will result in more favorable outcomes for borrowers and local communities, while also reducing losses to the Enterprises and, therefore, to taxpayers," said FHFA Director Melvin Watt in a statement.

The rules come as Fannie's and Freddie's auctions get under way. Freddie has held auctions for loans with around $1 billion in unpaid principal. Fannie executives have said they're considering auctions but haven't yet had one.

"The problem is, what's the purpose of changing the rules midstream? The goal of an investor when he buys a nonperforming loan is already to make it perform," said Vincent Fiorillo, president of the board of the Association of Mortgage Investors and an executive at DoubleLine Capital.

Mr. Fiorillo said that investors would have to see the specifics of the next Fannie or Freddie loan auctions before knowing whether the rules would hurt prices.

New Jersey Community Capital, a nonprofit group that has purchased several hundred FHA-backed loans, said that it took a look at Freddie's recent auction but ultimately couldn't put together a bid.

Among the constraints, Freddie's bidding window--at two weeks--wasn't enough time for the nonprofit to inspect the properties or figure out where to get financing, said Peter Grof, deputy to the president at NJCC.

The size of the pools so far, at several hundred million dollars, have also been hard for nonprofits to swallow, he said.

Write to Joe Light at joe.light@wsj.com

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