In California, the courts have long called the gift of an engagement ring "implied conditional," and require its return on the breaking of the engagement by the recipient of the gift. However, if the man breaks the engagement, he cannot obtain the ring. California has a statute that provides that if the recipient of the ring or other gift calls the wedding off or the parties agree to not go forward, the donor of the ring, e.g., the fiance, is entitled to get it back. If the donor calls the wedding off unilaterally, common law applies. Check with a lawyer in your locale to discuss more of the details.
Good luck to you.
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