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Skylight generally maintains information for a maximum of 18 months. If the vessel has not transmitted on AIS at all in the last 18 months, then the Event History would appear blank. With AIS off, there is no possibility of capturing events on a specific vessel detail page.
If Skylight did not generate any events (e.g. Fishing, Standard Rendezvous, correlated Vessel Detection, Port Visit) for that vessel in the last 18 months, the Event History will appear blank except for the Last Known Position.
If Skylight believes this vessel is a buoy, it will not show any Event History as events are intended only for vessels. Last Known Position will not be available as well. Vessels that are classified as buoys by Skylight’s model will have a buoy icon next to “Vessel Type”:
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