We identified common functional hallmarks in B‐CLL and MBL phosphoproteomes, notably tonic signaling (low‐level, constitutive signaling) of the B‐cell antigen‐specific receptor (BCR) and nuclear factor NF‐kappa‐B (NF‐kβ)/signal transducer and activator of transcription 3 (STAT3) pathways. Here, STAT3 is linked to B-cell chronic lymphocytic leukemia.