KLM was not acquired by Air France. In May 2004, the two companies merged to form Air France-KLM. The former Air France and KLM became subsidiaries of this company, both of which operated independently and had their own brands.
The company is headquartered in Paris. Among the merged company names, the name of Air France ranks first, and the strength of Air France is much greater than that of KLM, so it gives people the impression that KLM has been acquired by Air France.
All KLM and Air France planes now have the words Air France-KLM.