4-Chloroisatoic anhydride is primarily used as an intermediate in the synthesis of various pharmaceuticals and organic compounds. It plays a key role in the production of active pharmaceutical ingredients (APIs), particularly in the development of drugs targeting neurological and inflammatory conditions. Additionally, it is utilized in the preparation of dyes and pigments due to its ability to form stable and vibrant colorants. In research, it serves as a building block for creating complex molecules, aiding in the study of chemical reactions and material properties. Its applications also extend to agrochemicals, where it contributes to the formulation of pesticides and herbicides.