Private banks are banks owned by either the individual or a general partner(s) with limited partner(s). Private banks are not incorporated. In any such case, creditors can look to both the "entirety of the bank's assets" as well as the entirety of the sole-proprietor's/general-partners' assets.
These banks have a long tradition in Switzerland, dating back to at least the Revocation of the Edict of Nantes (1685). Private banks also have a long tradition in the UK where C. Hoare & Co. has been in business since 1672.