This paper shows that the German legislator thought of the economic effects of sussession law in the year 1879. Equally, the French legislator and the French discussion considered some aspects that are econmomically relevant. The economic considerations concerned the right to a compulsory portion (German: Pflichtteilsrecht; French: la réserve). The legislator’s objective was to distribute wealth. The current criticism of this objective in Germany is not justified. The right to a compulsory portion implies several further economic aspects. It generates incentives for economic cooperation between family members and prevents them from externalizing costs (onto the social system). It reduces transaction costs and implifies the legal relationships between the members of the family. The fact that the right to a compulsory portion constitutes binding law does not necessarily decrease efficiency.