We were commissioned to make the map by the UCL Energy Institute, who had a research license from exactEarth for this historical AIS data.

If you press the little info button at the top right, you get some basic information, including this:

Where did you get the data and who paid?

Our data sources for shipping positions are exactEarth for AIS data (location/speed) and Clarksons Research UK World Fleet Register (static vessel information). We are very grateful to our funders, the European Climate Foundation.