Question: what is the difference between bone in rib roast and prime rib?
Answer: All Prime Ribs are Standing Rib Roasts, not all Standing Rib Roasts are Prime Rib. [see edit below] A "Prime Rib" is a standing rib roast, from a beef that has achieved a USDA Grade of "Prime". Bone-In or Bone-out are separate distinctions the can be applied to any standing rib roast, regardless of grade.