The significance to me of the Coase Theorem is that it undermines the Pigovian system.

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Mr Freeman cites the Coase theorem to show why this might be so.

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Since standard economic theory assumes transaction costs to be zero, the Coase Theorem demonstrates that the Pigovian solutions are unnecessary in these circumstances.

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The Coase Theorem essentially states that if trade in an externality is possible and there are no transaction costs, bargaining will lead to an efficient outcome regardless of the initial allocation of property rights.

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