A promise to set aside, dedicate and use exclusively for specified purposes certain categories of property, generally money or other intangibles.
See Also
A covenant that is the opposite of a pledge – a promise not to pledge property, generally money or other intangibles, to any party other than the issuer, a letter of credit provider or other intended beneficiary of the negative pledge.

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A requirement imposed under the Code to pay to the Internal Revenue Service an amount equal to the arbitrage earned on tax-exempt bonds.