The Brookings Institution has been promoting Innovation Districts as a useful geographical concept since 2014 (for example here and here). I should think that mapping Innovation Districts precisely would be part of that research and indeed some maps are shown here and there. However, I have not been able to find a unified source of shapefiles for US Innovation Districts (even though the research has focused on the US). Maybe the sources vary city by city or maybe shapefiles are not systematically available even for the cities covered by the initial study. What are sources of shapefiles for all Innovation Districts or failing that sources for existing ones?