Last summer Google transitioned maps made with Classic Google Maps and Google Maps Engine Lite to their new My Maps platform. This morning I received an email from the Google Maps team announcing that you need to export the KML files of your original maps or lose them on June 1st when all maps will be forced into the new My Maps formatting. If you're happy with the way that the new version of your maps looks, there is nothing that you need to do. If you want to store the original KML file then you will need to export that file. I created the video embedded below to demonstrate how to export KML files from Google Maps.