this is the writing form of the international patent classification system (IPC) class number, and its complete form is Int.Cl.C12P 19/12, and later C12P 19/12 is the category of IPC class number.
the international patent classification system establishes categories according to technical topics, and the classification table adopts hierarchical structure, which divides the whole technical field into five different levels in descending order, namely, department (such as C), large category (such as C12), small category (such as C12P), large group (such as C12P 19/) and small group (such as C12P 19/12).
therefore, IPC classification number C12P19/12 stands for disaccharide.