The United States once issued a 100,000-dollar gold certificate used only for official transactions between Federal Reserve Banks. These notes were never intended for general public circulation or private ownership. After being withdrawn, surviving certificates became tightly controlled government property, mainly held in museums, archives, or institutional collections. Laws and regulations prohibit individuals from legally owning these specific high-denomination certificates. The restriction reduces counterfeiting risks and reinforces that these notes were tools of interbank accounting rather than public currency. Collectors can still own other large but discontinued denominations that were legally circulated, such as 500- or 1,000-dollar bills.`