Nearly a year ago, even France admitted to having off-balance-sheet transactions and hiding debt.

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Off-balance-sheet transactions, widely used by Enron and employed by many companies for legitimate reasons, further obfuscate the picture.

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In February 2010, Greece admitted that through assistance from Goldman Sachs, it used off-balance-sheet transactions to hide its deficit and national debt.

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Other factors that might raise red flags include a high proportion of off-balance-sheet transactions, frequent changes in auditor and delays to earnings announcements.

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Re-hypothecation transactions are off-balance sheet and are therefore unrestricted by balance sheet controls.

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