The whole system relies on trust between brokers, rather than paper records or third party guarantees, with any shortfalls between what goes out and what comes in settled periodically.

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According to a recent report by the World Bank, private lenders have granted borrowers more flexibility with loan covenants and demanded fewer third-party guarantees.

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Clearly, though, as in the case of third-party guarantees on high-priced works, this is a much more attractive proposition for guarantors when art market confidence is pretty high as it is right now.

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One of these is the way in which auction houses use third-party guarantees, where an outside individual or company agrees in advance to pay a set amount for a work sold at auction, in return for a cut of proceeds if the consignment sells for more than that.

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