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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Hundreds of Terms and Concepts
A fund maintained to provide security to bondholders that does not exceed the least of (i) 10% of the stated principal amount of the bond issue (issue price if more than a de minimis amount of original issue discount or premium), (ii) the maximum annual principal and interest requirements of the bonds, or (iii) 125%…