Legal Question in Real Estate Law in California

If he isn't on title, he has no legal interest in the house they could attach.

(1) The lender can of course foreclose if it isn't paid. The lender could also, perhaps, enforce any "due on sale" type of clause in the loan because when he transferred his share of title to you (by gift, I'd guess), that would have triggered the due on sale provision and the lender can now call the loan rather than foreclose.

(2) The medical creditors might attack the transfer of your father's share to you as fraudulent under the Uniform Fraudulent Transfer Act, Civil Code sections 3439 to 3439.12. This law makes it illegal to transfer property for significantly less than fair market value if the purpose or effect is to hinder, defraud or delay any existing or feared future creditor of the transferor and the transferor has inadequate other resources to pay creditors. Without more financial information I could not say whether the transfer of ownership here would meet the tests set up in the UFTA, but if I were either of the two of you, I would want to review the UFTA's provisions, including the creditor remedies and penalties against the transferor and transferee to see if you have cause for concern. So, despite what Mr. Nelson says, I would say the medical creditors pose at least a moderate threat.

I disagree with Mr. Nelson and agree with Mr. Whipple.