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This may be an edge case, but if you look at this (admittedly ancient) Stack Overflow question that was migrated to Meta, you can see my old user name "Gortok" on the percentage of ownership under the question.
This appears to be a bug. But it could also be a feature. Even if it is a bug, I'm not sure it's one that needs to be fixed, since it only appears to affect migrated questions where the user has changed usernames — a rarity at best.