Weak Renegotiation-Proofness (WRP) singles out marginal cost pricing as a unique pure-strategy equilibrium of the infinitely repeated Bertrand duopoly. We show that, with a discrete strategy space, WRP does not eliminate any relevant subgame perfect equilibrium outcome

This paper analyzes the role of patience in a repeated Bertrand duopoly where firms bargain over which collusive price and market share to implement. It is shown that the least patient firm's market share is not monotone in its own discount factor