Collateralized Mortgage Obligations (CMOs) sometimes referred to as Real Estate Mortgage Investment Conduits (REMICs), are one of few innovative investment methods available in today's investment world. CMOs offer relative safety, regular payments and notable yield advantages over other better known fixed-income securities of comparable credit quality.

A wide variety of CMO securities with different cash flow and expected maturity characteristics have been designed to meet specific investment objectives. While CMOs offer advantages to investors, they also carry certain risks which will be further explained in this document. To determine if CMOs fit within your investment portfolio, you should first understand the distinctive features of these securities.

CMOs were first introduced in 1983. The Tax Reform Act of 1986 allowed CMOs to be issues in the form of REMICs, creating certain tax and accounting advantages for issuers and for certain large institutional and foreign investors. Today, almost all CMOs are issued in REMIC form. Remember that throughout this CMO explanation, REMICs and CMOs are interchangeable.

THE BUILDING BLOCKS OF CMOS

When a CMO is created, it begins with a mortgage loan extended by a financial institution (such as a savings and loan, commercial bank or mortgage company) to finance a borrower's home or other real estate. The homeowner usually pays the mortgage loan in monthly installments composed of both interest and "principal". Over the duration of the mortgage loan, the interest component of payments in the early years gradually declines as the principal component increases.

To obtain funds to generate more loans, lenders either "pool" groups of loans with similar characteristics to create securities or sell the loans to issuers of mortgage securities. The securities most commonly created from pools of mortgage loans are "mortgage pass-through securities" (MBS) or "participation certificates" (PCs). MBS represent a direct ownership interest in a pool of mortgage loans. As the homeowners whose loans are in the pool make their mortgage loan payments, the money is distributed on a pro rata basis to the holders of the securities.

Several factors can affect the homeowners' payments. Typically, the homeowner will "prepay" the mortgage loan by selling the property, refinancing the mortgage or otherwise paying off the loan in part or whole. Most mortgage pass-through securities are based on fixed-rate mortgage loans with an original maturity of 30 years, but experience shows that most of these mortgage loans will be paid off much earlier.

While the creation of MBS greatly increased the secondary market for mortgage loans by pooling them and selling interests in the pool, the structure of such securities has inherent limitations. MBSs only appeal to investors with a certain investment horizon - on average, 10-12 years.

CMOs were developed to offer investors a wider range of investment time frames and greater cash-flow certainty than had previously been available with MBS. The CMO issuer assembles a package of these MBS and uses them as collateral for a multiclass security offering. The different classes of securities in a CMO offering are known as tranches, from the French word for slice. The CMO structure enables the issuer to direct the principal and interest cash flow generated by the collateral to the different tranches in a prescribed manner, as defined in the offering's prospectus, to meet different investment objectives.

THE HIGH CREDIT QUALITY OF CMOS

The Government National Mortgage Association (GNMA, or Ginnie Mae) an agency of the U.S. government, along with U.S. government-sponsored enterprises (GSE) such as the Federal National Mortgage Association (FNMA, or Fannie Mae) or the Federal Home Loan Mortgage Corporation (FHLMC, or Freddie Mac), guarantee most MBSs. Ginnie Mae is a government-owned corporation within the Department of Housing and Urban Development. Fannie Mae and Freddie Mac have federal charters and are subject to some oversight by the federal government, but are publicly owned by stockholders.

Fannie Mae and Freddie Mac issue and guarantee pass-through securities. Ginnie Mae only adds its guarantee to privately issued pass-throughs backed by government issued (FHA and VA) mortgages. Fannie Mae and Freddie Mac have issues CMOs for quite some time; the Department of Veterans Affairs (VA) began to issue CMOs in 1992, and Ginnie Mae initiates its own CMO program which began in 1994. Securities guaranteed or guaranteed and issues by these entities are known generically as "agency" mortgage securities. The agency guarantees enhance their credit quality for investors. In addition, the mortgages backing Fannie Mae and Freddie Mac mortgage securities must meet strict quality criteria. Those backing GNMA pass-throughs are underwritten in accordance with the rules and regulations of the FHA and the VA, which insure them against default.

The extent of the agency guarantee depends on the entity making it. Ginnie Mae, for example, guarantees the timely payment of principal and interest on all of its mortgage securities, and its guarantee is backed by the "full faith and credit" of the U.S. government. Holders of Ginnie Mae mortgage securities are therefore assured of receiving payments promptly each month, regardless of whether the underlying homeowners make their payments. They are guaranteed to receive the full return of face-value principal even if the underlying borrowers default on their loans. Mortgage securities issued by the VA carry the same full faith and credit U.S. government guarantees.

Fannie Mae guarantees timely payment of both principal and interest on its mortgage securities whether or not the payments have been collected from the borrowers. Freddie Mac also guarantees timely payment of both principal and interest on its Gold PCs and CMOs. Some older series of Freddie Mac PCs guarantee timely payment of interest, but only the eventual payment of principal. Although neither Fannie Mae or Freddie Mac securities carry the additional full faith and credit U.S. government guarantee, the credit markets consider the credit on these securities to be equivalent to that of securities rated triple-A or better.

Some private institutions, such as subsidiaries of investment bank, financial institutions and home-builders, also issue mortgage securities. When issuing CMOs, they often use agency mortgage pass-through securities as collateral; however, their collateral may include different or specialized types of mortgage loans and/or pools, letters of credit and other types of credit enhancements. These private-labeled CMOs are the sole obligation of their issuer. To the extent that private-label CMOs use agency mortgage pass-through securities as collateral, their agency collateral carries the respective agency's guarantees. Private-label CMOs are assigned credit ratings by independent credit agencies based on their structure, issuer, collateral and any guarantees or outside factors. Many carry the highest AAA credit rating.

As an additional investor protection, the CMO issuer typically segregates the CMO collateral or deposits it in the care of the trustee, who holds it for the exclusive benefit of the CMO bondholders.

A DIFFERENT SORT OF BOND

Although CMOs entitle investors to payments of principal and interest, they differ from corporate bonds and Treasury securities in significant ways. Corporate and Treasury bonds are issued with stated maturities. The purchase of a bond from an investor is essentially a loan to the issuer in the amount of the principal, or face amount, of the bond for a prescribed period of time in return for a specified annual rate of interest. The bondholder receives interest, generally in semiannual payments, until the bond is redeemed. When the bond matures, or is called by the issuer, the issuer returns face value of the bond to the investor in a single principal payment.

For the complete 18 page article on everything you would ever want to know about CMOs, visit the investors educational website at InvestorEarth.com.