Merging individual sets resulted in 4,466 structurally distinct probe compounds (i.e. as unique InChIKeys). This includes 940 (21%) experimental plus 3,670 (82.2%) calculated probes including 3,178 from Probe Miner. The overlap of 143 (3.2%) compounds is mainly due to the inclusion of the Chemical Probes Portal in the Tool Compound Set. The full 4,466 set includes 275 labelled as drugs (reported to be in clinical phases) with 103 labelled as approved by FDA, EMA and other agencies. The full set also includes 29 PROTACs (Proteolysis Targeting Chimeras) from PROTAC-DB and Chemical Probes Portal, 60 covalent binders from CovalentInDB , and 21 biased GPCR ligands from BiasDB .