TNF receptor superfamily member 11b encoded by TNFRSF11B is a member of the TNF-receptor superfamily. TNF receptor superfamily member 11b is an osteoblast-secreted decoy receptor that functions as a negative regulator of bone resorption. TNF receptor superfamily member 11b specifically binds to its ligand, osteoprotegerin ligand, both of which are key extracellular regulators of osteoclast development. Studies of the mouse counterpart also suggest that TNF receptor superfamily member 11b and its ligand play a role in lymph-node organogenesis and vascular calcification. Alternatively spliced transcript variants of TNFRSF11B have been reported, but their full length nature has not been determined.