Structured investment vehicle

A structured investment vehicle (SIV) is a non-bank financial institution established to earn a credit spread between the longer-term assets held in its portfolio and the shorter-term liabilities it issues with high leverage. They are simple credit spread lenders, frequently "lending" by investing in securitizations, but also by investing in corporate bonds and funding by issuing commercial paper and medium term notes, which were usually rated AAA until the onset of the financial crisis. They did not expose themselves to either interest rate or currency risk and typically held asset to maturity. SIVs differ from asset-backed securities and collateralized debt obligations (CDOs) in that they are permanently capitalized and have an active management team. They do not wind-down at the end of their financing term, but roll liabilities in the same way that traditional banks do.

They are generally established as offshore companies and so avoid paying tax and escape the regulation that banks and finance companies are normally subject to. In addition, until changes in regulations around 2008, they could often be kept off the balance-sheet of the banks that set them up, escaping even indirect restraints through regulation. Due to their structure, the assets and liabilities of the SIV was more transparent than traditional banks for investors. SIVs were given the label by Standard & Poors -- Moody's called them "Limited Purpose Investment Companies" or "LiPICs". They are considered to be part of the non-bank financial system, which has two parts, the shadow banking system comprising the "bank sponsored" SIVs (which operated in the shadows of the bank sponsors balance sheets) and the parallel banking system, made up from independent (i.e. non bank aligned) sponsors.

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