Consider a set, E, of all possible exit vectors for a given scaffold. Since there are many possible EVPs for a given set of compounds with a shared scaffold, each EVP is a subset of exit vectors, which can be denoted as 𝑣 ∈ 𝐸. For an ensemble of molecules, we obtain a set of sets containing all of the EVPs, i.e., 𝑉 = {𝑣 1 , . . . , 𝑣 𝑁 } . Since EVP does not take into account the identity of the individual substituents, different molecules can have the same EVPs, i.e. 𝑣 𝑖 = 𝑣 𝑗 | 𝑖 ≠ 𝑗. Once EVPs are calculated for a set of molecules, various statistics can be obtained, which we introduce and define now using Figure , which shows an exemplar scaffold (top) and four associated molecules (bottom row). nEXIT refers to the total number of exit vectors available within a molecular scaffold (nEXIT = 5 for the scaffold in Figure ). nEVPS denotes the number of unique EVPs exemplified by a set of molecules within a single scaffold family (i.e., this equals 3 for the four molecules shown in the lower part of Figure ). %EXPLOITED is the percentage of exit vectors that are exploited across a set of molecules within a single scaffold family (i.e., it is calculated as 𝑛𝐸𝑉𝑃𝑆 𝑛𝐸𝑋𝐼𝑇 × 100; this value is 60% across the four molecules shown in the lower part of Figure ). We label the degree of exploitation of each EVP as dEVP (which is equal to 1, 1, 2, and 2 respectively for the four molecules shown in the lower part of Figure ). Finally, max(dEVP) is the highest EVP cardinality across a given set of molecules (this equals 2 for the four molecules shown in the lower part of Figure ). Data Acquisition. ChEMBL32 was used for the Fragment Library and the Exploited Vector Pattern Diversity Sampling Datasets. ChEMBL33 was used for the SAR Analysis Dataset. These datasets are provided as part of the Supplementary Information.