New Hampshire is a state that views the engagement ring as a conditional gift. A man presents an engagement ring, and the woman accepts it, on the condition that they will marry. If they breakup, a necessary condition for her keeping the ring (i.e. marriage) has not been met, and she must return the ring to him.
See, Gikas v. Nicholis, 71 A.2d 785, 786 (N.H. 1950)
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