• Additional information including detailed experimental methods, description of the Reversible covalent BTK PROTAC library and its degradation results in two cell lines, BTK degradation by PROTACs in Ramso cells, data on cellular penetration of PROTACs, time dependency of BTK degradation, validation of CRBN mediated degradation, kinetic studies of BTK labeling using LC/MS, and GSH effect on labeling, proteomics selectivity analysis for the PROTACs at additional concentrations, B cell receptor signaling inhibition data, detailed synthetic protocols for preparation of compounds with high resolution mass spectrometry and NMR analysis (PDF).