Abstract: A system and method are disclosed. The method includes receiving, at a server computer, a transaction clearing request for a transaction, and then determining, using the server computer, if the transaction satisfies a stored blocking parameter. The method further includes allowing, using the server computer, the transaction clearing request if the transaction does not satisfy the stored blocking parameter, and denying, using the server computer, the transaction clearing request if the transaction satisfies the stored blocking parameter. In B2B transactions, clearing requests that are less than (or slightly above) a previously contracted amount can be denied because they are less than what the buyer expected.