For the Islamic Republic, the politics of welfare and the problem of social order and security are inextricably intertwined. Media and scholarly accounts of Iranian society stress its youthful demographic structure and its frustrated middle classes. Yet Iran's baby boom ended in the 1990s and the country's average birth rate is now under replacement levels. Consequently, the predicaments of aging and generational security loom in Iran's future. Most of the pension funds allocated to care for this generation are held by large organizations that act as massive investment conglomerates, and have been highly active in acquiring state-owned enterprises auctioned off over the past decade's privatization program heralded by the supposedly populist President, Mahmoud Ahmadinejad. As a result, Iran's formal labor force, like Brazil's union workers, or even closer to the West, California's nurses, is now heavily invested in stocks, bonds, and other assets. How did the Islamic Republic end up on the cutting edge of what Robin Blackburn has labeled "grey capitalism" - capitalism heavily reliant on the reinvestment of pension funds? Utilizing interviews from the Social Security Organization in Tehran and primary literature collected during fieldwork in the country from 2009-11, this paper traces the institutional origins and models of Iran's social security system, its fate during the early years of the Islamic Republic, and its role in the security and livelihoods of the country's middle classes today. In doing so, I show that the politics of the Green Movement, the 2009 uprisings against perceived fraudulent presidential elections, are deeply embedded in Iran's social security system and its contradictions.