Visa earns data processing revenues from the authorization, clearing, settlement, transaction processing services and other maintenance and support services that facilitate transaction and information processing among customers globally and Visa Europe.

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Instead of charging a fixed transaction fee for clearing the rights, Corbis tries to buy low and sell high, capturing the spread as revenue.

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Furthermore, processing costs are low: about 30 cents per transaction, half the cost of clearing a cheque.

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"Defendants effectively operated in a tag-team fashion--rotating in the roles of prime broker, clearing agent or counterparty that enabled the short sale transaction to go forward without the expectation of delivery, " the complaint says.

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The important benefit of exchange clearing is a clearing house acts as the central counterparty to both sides of a CDS transaction, thereby reducing risk on both sides of the transaction.

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Visa earns revenues by charging fees for its transaction processing service, which involves routing payment information to facilitate the authorization, clearing and settlement of transactions.

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