A Monopsony is a market form where there is only one buyer, but many sellers. Much like with the monopoly this single buyer has a complete influence on the price. In practice, this market form does not occur often. One example may be a healthcare system where there is only one "buyer" of healthcare services; which is usually the state, or a state-run institution. Another example is defense industry, where the state is the often only buyer. Still another is that of public transport: Either the whole public transport is run by one (usually state-owned) company, or the state awards contracts to run a given line for a certain time period.

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