In the period of “new” imperialism in the late nineteenth and early twentieth centuries, France strived to create a sphere of influence in southwest China. To foster such imperialist policies, France’s policy makers regarded French companies operating in East Asia as instrumental. One such firm was Auguste Raphael Marty’s Tonkin Shipping Company, based in Haiphong, French Indochina, which operated steam coasters across the wider Gulf of Tonkin region. In the region’s highly competitive shipping market, Marty strived to achieve a monopoly when favorable conditions permitted during the final phase of the Sino-Japanese War. His profit-driven strategy caused huge losses for Chinese shippers and ultimately resulted in their boycotting his ships through the Tsap Yet syndicate. When French officials intervened on Marty’s behalf in negotiations with the Chinese government, the Syndicate was finally dissolved. It was followed by an agreement between the Chinese firm of Yuen Cheong Lee and Co. and the German firm of Jebsen and Co., based on long-established mutual trust between the owners. Although Marty received monetary compensation for his losses, he ruined his relationship with Chinese merchants. This case study presents little-known facts about the interactions among foreign firms in China and demonstrates the Chinese ability to react efficiently to unfair business practices. Keywords: French imperialism, Chinese shipping business, Southwest China, Gulf of Tonkin, Hoihow, Pakhoi, Haiphong, Western tramp shipping, Tonkin Shipping Company, Marty et d’Abbadie, Auguste Raphael Marty, Yuen Cheong Lee and Co., Jebsen and Co., Schomburg and Co., Tsap Yet Syndicate, Sir Robert Hart, Edmund Baron von Heyking, Kwang-chow-wan, Kiaochow