The inelastic markets hypothesis states that the aggregate stock market price elasticity of demand is small, implying that flows have large impacts on prices. We exploit demand shocks created as investor funds are frozen and unfrozen during Chinese IPOs to estimate the impact of demand shocks on the Chinese stock market. Using brokerage account records, we observe the selling and buying as investors raise cash to subscribe for IPOs and then reinvest the funds that supported unsuccessful subscriptions. Using an instrumental variables estimator we find that a 10 bps demand shock increases stock prices by between 30 and 48 bps.