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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The custodian of funds held in the escrow fund and responsible for holding and managing the escrow fund, including any investments in the escrow fund, up to and including the date when the refunded bonds mature or redeemed, whichever is earlier.