This paper examines the bargaining over how to combine lists of candidates between rounds of the 2004 and 2010 French regional elections. Regressions support the hypothesis that a party's fraction of a coalition's total seats won will be equal to that party's fraction of the total first-round vote of all parties represented in the combined list. However, there is a slight tendency for small parties to get less than implied by this hypothesis. This is the opposite of what is commonly found in studies of coalition formation in parliamentary systems. The paper provides some support for the hypothesis that this is due to the electoral rules determining when a party is allowed to maintain their list in the second round. Finally, this paper examines properties of the function describing how a combined list divides any number of seats won.