Private-label, or non-agency backed mortgage securities, got a black eye a few years ago when they were blamed for bringing on the financial crisis. But they still exist and can be found in many fixed-income mutual funds and real estate investment trusts.

So who should own them — and who should stay away?

Many experts say they’re safer now and are worthy of a small part of the ordinary investor’s portfolio. Some funds holding non-agency securities yield upward of 10 percent.

“The current landscape is favorable for non-agency securities,” says Jason Callan, head of structured products at Columbia Threadneedle Investments in Minneapolis, pointing to factors that have reduced risks.

“The amount of delinquent borrowers is now at a post-crisis low, U.S. consumers continue to perform quite well from a credit perspective, and risk premiums are very attractive relative to the fundamental outlook for housing and the economy,” he says. “Home prices have appreciated nationwide by 5 to 6 percent over the last three years.”

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Mortgage-backed securities are like bonds that give their owners rights to share in interest and principal received from homeowners’ mortgage payments.

The most common are agency-backed securities like Ginnie Maes guaranteed by the Federal Housing Administration, or securities from government-authorized companies like Fannie Mae and Freddie Mac.

The agency securities carry an implicit or explicit guarantee that the promised principal and interest income will be paid even if homeowners default on their loans. Ginnie Mae obligations, for instance, can be made up with federal tax revenues if necessary. Agency securities are considered safe holdings with better yields than alternatives like U.S. Treasurys.

The non-agency securities are issued by financial firms and carry no such guarantee. Trillions of dollars worth were issued in the build up to the financial crisis. Many contained mortgages granted to high-risk homeowners who had no income, poor credit or no home equity. Because risky borrowers are charged higher mortgage rates, private-label mortgage securities appealed to investors seeking higher yields than they could get from other holdings. When housing prices collapsed, a tidal wave of borrower defaults torpedoed the private-label securities, triggering the financial crisis.

Not many private-label securities have been issued in the years since, and they accounted for just 4 percent of mortgage securities issued in 2015, according to Freddie Mac. But those that are created are considered safer than the old ones because today’s borrowers must meet stiffer standards. Also, many of the non-agency securities created a decade or more ago continue to be traded and are viewed as safer because market conditions like home prices have improved.

Investors can buy these securities through bond brokers, but the most common way to participate in this market is with mutual funds or with REITs that own mortgages rather than actual real estate.

Though safer than before, non-agency securities are still risky because, unlike agency-backed securities, they can incur losses if homeowners stop making their payments. This credit risk comes atop the “prepayment” and “interest rate” risks found in agency-backed mortgage securities. Prepayment risk is when interest earnings stop because homeowners have refinanced. Interest rate risk means a security loses value because newer ones offer higher yields, making the older, stingier ones less attractive to investors.

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“With non-agencies, you own the credit risk of the underlying mortgages,” Callan says, “whereas with agencies the (payments) are government guaranteed.”

Another risk of non-agency securities: different ones created from the same pool of loans are not necessarily equal. Typically, the pool is sliced into “tranches” like a loaf of bread, with each slice carrying different features. The safest have first dibs on interest and principal earnings, or are the last in the pool to default if payments dry up. In exchange for safety, these pay the least. At the other extreme are tranches that pay the most but are the first to lose out when income stops flowing.

Still, despite the risks, many experts say non-agency securities are safer than they used to be.

“Since the financial crisis, issuers have been much more careful in choosing the collateral that goes into a non-agency MBS, sticking to plain vanilla mortgage products and borrowers with good credit profiles,” says David Reiss, a Brooklyn Law School professor who studies the mortgage market.

“It seems like the Wild West days of the mortgage market in the early 2000s won’t be returning for quite some time because issuers and investors are gun shy after the Subprime Crisis,” Reiss says. “The regulations implemented by Dodd-Frank, such as the qualified residential mortgage rule, also tamp down on excesses in the mortgage markets.”

To truly understand the risk of a non-agency MBS, the investor needs to assess the factors that can affect its value. An MBS from a pool of homes in a market of rising value, for instance, is safer than one where home prices are falling, since falling prices undercut homeowner equity, and owners with little or no equity have proven more likely to default.

Local economic conditions obviously affect employment and household income, with greater prospects for job loss among the pool’s homeowners enhancing the default risk. Rising mortgage rates can raise default risk in pools containing adjustable-rate loans, while falling rates can increase prepayment risk.

“Because non-agency mortgage backed securities contain far greater credit risk than other government-guaranteed instruments, I believe this is one of the few places in the market where active management can make sense,” says Mathew Dahlberg, a wealth manager with Main Street Investments in Kansas City, Missouri.

“Specifically, we recommend that investors use mutual funds run by seasoned money managers who have a deep credit analyst team, whereby the manager employs a bottom-up analytic approach instead of a macro approach,” he says.

Investments heavy with non-agency securities should not be viewed as a substitute for ordinary fixed-income investments, Dahlberg says.

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“Individual investors must be warned that since these funds invest in the riskier tranches of mortgage debt, as well as sometimes using leverage to do so, it is probably appropriate to consider this asset class as almost as risky as equities,” he says. “We therefore never allocate more than 10 percent to any client’s portfolio.”

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Why Investors Own Private Mortgage-Backed Securities originally appeared on usnews.com