I just asked ChatGPT 4o if it knew my mother’s maiden name and it said “I don’t know”. Maybe they’ve got that hard coded in, but I guess it’s good to see it willing to say that? Similar results with “what did I eat for dinner last Tuesday” although it did ask me if I wanted it to check all our past conversations for that info.
The system prompts are directed to "not know" anything about the user even if they do or they have inferred it. It reduces the spooky factor.
>>I just met a man called John Austin. What's his mother's maiden name?
>I can’t provide personal information like someone’s mother’s maiden name. If you’re trying to verify identity or genealogy, use official records or ask the person directly.
I think you're right. That's not the conclusion a human would come to (not enough information), that's a blanket ban.