This article describes that in FortiWeb after an exception is added in a signature for a false positive trigger of the signature, there will be no more attack log for the false positive trigger of the signature.
If it is still desired to keep track of the traffic which has been exempted, it can still be recorded in the traffic log.
For example, originally there was a false positive trigger of the signature 040000137.
Then exception was added for client IP 184.108.40.206 in the signature.
After that, there was no more attack log found for this signature for the client 220.127.116.11, but the traffic log still existed (if the traffic log has been enabled).