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Economic sanctions against Iran, such as the embargo against Iranian crude oil, have affected the economy. Sanctions have led to a steep fall in the value of the rial, and as of April 2013 one US dollar is worth 36,000 rial, compared with 16,000 in early 2012. Following a successful implementation of the 2015 nuclear and sanctions relief deal, the resulting benefits might not be distributed evenly across the Iranian economy as political elites such as the Islamic Revolutionary Guard Corps have garnered more resources and economic interests.

What would possibly prevent the even spread of relief benefits from Iran's nuclear and sanctions deal of 2015?
the Islamic Revolutionary Guard Corps