Bonyads are charitable trusts in Iran that play a major role in Iran's non-petroleum economy, controlling an estimated 20% of Iran's GDP, and channeling revenues to groups supporting the Islamic Republic. Exempt from taxes, they have been called "bloated", and "a major weakness of Iran’s economy", and criticized for reaping "huge subsidies from government", while siphoning off production to the lucrative black market and providing limited and inadequate charity to the poor.