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A power of appointment that is conferred on an individual by name, rather than to a trustee, along with a duty to exercise that power. For example, very often a trust will authorize a person free of the trust to dispose of the trust property in his or her will; in such a situation it is expected that the power will be exercised. Potential beneficiaries may attempt to compel the exercise of this power in the courts, a move that would be unusual in the case of a power of appointment, where there is generally no such duty placed on the donee.

See also power of appointment, power nominatum.