Negative external confirmation request: a request that the confirming party responds directly to the auditor only if the confirming party disagrees with the information provided in the request.
A negative confirmation request asks the respondent to reply only in the event of disagreement with the information provided
Negative confirmation requests are expected to provide less reliable audit evidence than the use of positive confirmation requests. The auditor does not know whether non-response means agreement or merely that the accounts receivables have not bothered to respond. The auditor usually considers performing other substantive procedures to supplement the use of negative confirmations.