Is it illegal to own a $10,000 dollar bill?

Could you please clarify for me, is it actually against the law for someone to possess a currency note with a face value of $10,000? I understand that such large denomination bills were once circulated, but I'm wondering if their ownership is now considered illicit in any way. Additionally, are there any restrictions or regulations surrounding the ownership of such notes that I should be aware of? Thank you for your insight on this matter.