The sale comes with the agreement that the seller will repurchase the securities at a higher price.

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If they sell bonds they do not own, then they can use a repurchase agreement to ensure that they will have the securities they have agreed to deliver in the future.

ECONOMIST: Repurchase agreements

Reverse repurchase agreements involve the sale by the Fed of securities from its portfolio with an agreement to buy the securities back at a slightly higher price at a later date.

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