Enamine, ChemDiv, and Life Chemicals had a higher percentage of "Fragments RO3" (67.1%, 23.1 %, and 22.6%, respectively) than Maybridge and CRAFT (19.8% and 14.6%, respectively). Not surprisingly the proportion of fragments that fulfill the RO3 in the chemical vendors (between 2.6 and 67.1%) is higher than the same type of fragments in NP libraries (1.5% and 2.5%).