Personal opinion: NIB means the same as new-old stock. Complete, original, with box, paperwork, and implements, and unfired. Essentially in the condition it left the factory. LNIB and ANIB seem equivalent terms to me, but the gun has been fired a small amount, but all-original, with box, paperwork, and implements. Will show some evidence of firing on the cylinder face, and may have some indication of the beginnings of a cylinder turn line. Otherwise, no metal or wood finish defects.