Vitamin K dependent factors are those that require Vitamin K for their synthesis in the liver. Vitamin K is an important factor to gamma-glutamyl carboxylase which adds a carboxyl group to glutamic acid residues on factors II, VII, IX and X, as well as Protein S, Protein C. In adding the gamma-carboxyl group to glutamate residues on the immature clotting factors Vitamin K is itself oxidized. Deficiency of Vitamin K due to malabsorption, liver disease, etc. may contribute to bleeding disorders because clotting factor maturation depends on Vitamin K.

Which of these coagulation factors are referred to as "vitamin-K dependent?"