securitization represents an alternative and diversified source of
finance based on the transfer of credit risk (and possibly also
interest rate and currency risk) from issuers to investors.
In a more recent refinement, the reference portfolio is
divided into several slices, called tranches, each of which
has a different level of risk associated with it and is sold
separately. Both investment return (principal and inter-
est repayment) and losses are allocated among the various
tranches according to their seniority. The least risky tranche,
for example, has first call on the income generated by the
underlying assets, while the riskiest has last claim on that
income. The conventional securitization structure assumes
a three-tier security design—junior, mezzanine, and senior
tranches. This structure concentrates expected portfolio
losses in the junior, or first loss position, which is usually the
smallest of the tranches but the one that bears most of the
credit exposure and receives the highest return. There is lit-
tle expectation of portfolio losses in senior tranches, which,
because investors often finance their purchase by borrow-
ing, are very sensitive to changes in underlying asset qual-
ity. It was this sensitivity that was the initial source of the
problems in the subprime mortgage market last year. When
repayment issues surfaced in the riskiest tranches, lack of
confidence spread to holders of more senior tranches—
causing panic among investors and a flight into safer assets,
resulting in a fire sale of securitized debt.
Securitization was initially used to finance simple, self-
liquidating assets such as mortgages. But any type of asset
with a stable cash flow can in principle be structured into a
reference portfolio that supports securitized debt. Securities
can be backed not only by mortgages but by corporate and
sovereign loans, consumer credit, project finance, lease/trade
receivables, and individualized lending agreements. The
generic name for such instruments is asset-backed securi-
ties (ABS), although securitization transactions backed by
mortgage loans (residential or commercial) are called mort-
gage-backed securities. A variant is the collateralized debt
obligation, which uses the same structuring technology as an
ABS but includes a wider and more diverse range of assets.
The allure of securitizing
Securitization started as a way for financial institutions and
corporations to find new sources of funding—either by mov-
ing assets off their balance sheets or by borrowing against
them to refinance their origination at a fair market rate. It re-
duced their borrowing costs and, in the case of banks, lowered
regulatory minimum capital requirements.
For example, suppose a leasing company needed to raise
cash. Under standard procedures, the company would take
out a loan or sell bonds. Its ability to do so, and the cost,
would depend on its overall financial health and credit rating.
If it could find buyers, it could sell some of the leases directly,
effectively converting a future income stream to cash. The
problem is that there is virtually no secondary market for
individual leases. But by pooling those leases, the company
can raise cash by selling the package to an issuer, which in
turn converts the pool of leases into a tradable security.
Moreover, the assets are detached from the originator’s
balance sheet (and its credit rating), allowing issuers to raise
funds to finance the purchase of assets more cheaply than
would be possible on the strength of the originator’s balance
sheet alone. For instance, a company with an overall “B” rat-
ing with “AAA”-rated assets on its books might be able to
raise funds at an “AAA” rather than “B” rating by securitizing
those assets. Unlike conventional debt, securitization does
not inflate a company’s liabilities. Instead it produces funds
for future investment without balance sheet growth.
Investors benefit from more than just a greater range of
investible assets made available through securitization. The
flexibility of securitization transactions also helps issuers tai-
lor the risk-return properties of tranches to the risk tolerance
of investors. For instance, pension funds and other collective
investment schemes require a diverse range of highly rated
long-term fixed-income investments beyond what the pub-
lic debt issuance by governments can provide. If securitized
debt is traded, investors can quickly adjust their individual
exposure to credit-sensitive assets in response to changes in
personal risk sensitivity, market sentiment, and consumption
preferences at low transaction cost.
Sometimes the originators do not sell the securities out-
right to the issuer (called “true sale securitization”) but
instead sell only the credit risk associated with the assets
without the transfer of legal title (“synthetic securitization”).
Synthetic securitization helps issuers exploit price differences
between the acquired (and often illiquid) assets and the price
investors are willing to pay for them (if diversified in a greater
pool of assets).
Growth of securitization
The landscape of securitization has changed dramatically in
the last decade. No longer is it wed to traditional assets with
specific terms such as mortgages, bank loans, or consumer
loans (called self-liquidating assets). Improved modeling and
risk quantification as well as greater data availability have
encouraged issuers to consider a wider variety of asset types,
including home equity loans, lease receivables, and small
business loans, to name a few. Although most issuance is
concentrated in mature markets, securitization has also reg-
istered significant growth in emerging markets, where large
and highly rated corporate entities and banks have used secu-
ritization to turn future cash flow from hard-currency export
receivables or remittances into current cash.
In the future, securitized products are likely to become
simpler. After years of posting virtually no capital reserves
against highly rated securitized debt, issuers will soon be
faced with regulatory changes that will require higher capital
charges and more comprehensive valuation. Reviving securi
-
tization transactions and restoring investor confidence might
also require issuers to retain interest in the performance of
securitized assets at each level of seniority, not just the junior
tranche. n
Andreas Jobst is an Economist in the IMF’s Monetary and
Capital Markets Department.
Finance & Development September 2008 49