Identifier passes all its sightings through the SmartVis Face Alarm Service which then processes them and sends them to SmartVis Face Server. This even includes sightings that have been merged by Identifier, i.e. the configuration setting SightingsMerged has been set to true in the Identifier configuration file.
The SmartVis Face Alarm service has a sophisticated logic engine which processes the alarms. By default it is configured to filter out sightings of the same identity if they appear within a certain time period. The main configuration setting for this is delay_between_2 which can be found in the Alarm Service configuration file. By default this is set to 60 seconds. So, by default, any new sighting of the same subject from the same Identifier will not be sent to SmartVis Face Server if the gap between the two sightings is less than 60 seconds.
In cases, like these the list of sightings shown in Identifier will differ slightly than those shown in SmartVis Face Server.