Scrutable

Transparify ranked it third largest UK think tank by expenditure, but gave it its lowest rating, 'deceptive', on funding transparency.[2]

In 2016, The Guardian reported that IISS "has been accused of jeopardising its independence after leaked documents showed it has secretly received £25m from the Bahraini royal family", noting that leaked "documents reveal that IISS and Bahrain’s rulers specifically agreed to keep the latter’s funding for the Manama Dialogues secret".[7][8] The IISS did not dispute the authenticity of the leaked documents or deny receiving funding from Bahrain, but issued a response stating that "[a]ll IISS contractual agreements, including those with host governments, contain a clause asserting the Institute’s absolute intellectual and operational independence as an international organisation that does not participate in any manner of advocacy."[9] The Middle East Eye subsequently reported that IISS may have received nearly half of its total income from Bahraini sources in some years.