Google Earth Enterprise announced to become open source under the Apache 2.0 license by the end of March this year. The official announcement was made on Jan 30, 2017. It will be available to the global community of developers on github.com. This will let organisations to deploy Google Maps and Google Earth in their on-premises data center infrastructure.
But making the server software available for free may have diverse effects on the geospatial world. Many geospatial software providers may get a tough competition as GEE becomes open source.
Picture Courtesy: https://www.google.com/earth/