Clearing Corporation

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Definition of 'Clearing Corporation'
An organization associated with an exchange to handle the confirmation, settlement and delivery of transactions, fulfilling the main obligation of ensuring transactions are made in a prompt and efficient manner.  They are also referred to as "clearing firms" or "clearing houses". 
Investopedia explains 'Clearing Corporation'
In order to make certain that transactions run smoothly, clearing corporations become the buyer to every seller and the seller to every buyer. In other words, they take the offsetting position with a client in every transaction.