A count of ring systems, both aromatic and aliphatic, yielded 39,036 unique ring systems in SAVI products. Rings that were already present in the building blocks were also counted. We compared the SAVI ring system count with the ring systems found in three large databases (Table ). We note that the REAL database, while of similar size as SAVI, and based on essentially the same building block set, contain less than a tenth of the number of ring systems found in SAVI. This is likely due to the fact that the chemistries involved in creating SAVI contained more ring-forming transforms than those used for REAL. PubChem, a very diverse database aggregated from hundreds of sources with very different types of compounds, shows a much larger number of different ring systems. Yet, the iRL, also combining hundreds of sources (but only of screening samples), only slightly surpasses SAVI. Perhaps most interestingly, the overlap subsets of SAVI comprised only a few thousand cases for each of the three databases (PubChem: 3,295; REAL: 2,145; iRL: 2,883) while the ring systems present only in SAVI added up to 35,623.