We propose a theory of inefficient renegotiation that is based on loss aversion. When two parties write a long-term contract that has to be renegoti- ated after the realization of the state of the world, they take the initial contract as a reference point to which they compare gains and losses...

For the procurement of complex goods the early exchange of information is important to avoid costly renegotiation ex post. We show that this is achieved by bilateral negotiations but not by auctions. Negotiations strictly outperforms auctions if sellers are likely to have superior information...