If the US debt we hold is denominated in US dollars, it is usually settled in US dollars when we sell these US debts. During the transaction, the seller will transfer the US dollars from the sale of US debt to his bank account, and the buyer will pay the corresponding US dollars to the seller.

As for who owns these dollars, it can be understood that each bank has a corresponding bank account, and banks will also settle funds through different settlement channels. For example, in the United States, funds between banks are usually settled through the Federal Reserve Bank, while internationally, funds can be transferred and cleared through international settlement systems such as SWIFT. Therefore, the US dollars obtained from the sale of US debt may be deposited in the bank account used by the seller, or settled and managed by the local bank using a specific settlement channel.