Indeed, it remains of prime importance to investigate whether BiP has independent effects on the osteoclast lineage in vivo in view of the current notion that there are molecular differences between subsets of osteoclasts associated with either normal bone resorption/turnover or those associated with different pathologies, such as RA or even cancer‐induced bone loss 35, 36, 37, 38. Here, HSPA5 is linked to cancer.