Is a man's claim of marriage to a young female in his custody accepted?

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A man's claim of marriage to a young female in his possession is not accepted, nor is she left alone with him. This ruling applies because possession establishes ownership (*yad*), but a claim of marriage necessitates that she is free or not owned by him, and possession does not establish ownership over a free person. If the female grows up and testifies to the marriage, her testimony is accepted.