This paper explores the relationship between French antitrust and labor law following passage of the revolutionary Le Chapelier law by the National Constituent Assembly in 1791. The Le Chapelier law reaffirmed the abolition of the guild system and prohibited all corporate professional bodies and coalitions of workers in broad, sweeping terms. Article 419 of the 1810 Penal Code similarly punished coalitions of merchants and sellers. As I show, French jurists initially relied on the revolutionary history and language of Le Chapelier to clarify the purpose and scope of Article 419. In doing so, they tied the two laws together both discursively and doctrinally. Ideas regarding the spirit of association, the validity of collective economic interests, and the legitimacy of “defensive” coalitions first introduced in the antitrust context were appropriated by workers movements, who used them to legitimize their own existence and push for labor reforms, including the ability to strike. Liberalization of the Le Chapelier law in turn weakened the strictures of Article 419; the wholesale abolition of Le Chapelier in 1884 led contemporary legal observers to conclude that Article 419 was a dead letter, thus facilitating the concentration and cartelization of French business at the end of the century.