III receives funding for its advocacy for the creation of an International Anti-Corruption Court from the Sigrid Rausing Trust, the Climate Change Collaboration (Aurora Trust, JJ Charitable Trust & Mark Leonard Trust), the MacArthur Foundation, the Rockefeller Brothers Fund and the Wayfarer Foundation, among others.

III has previously received two grants from the National Endowment for Democracy to support its work in Ukraine and programs associated with the III Youth Leaders Network.