Tyrosine specific kinases form a large family of enzymes that are responsible for catalyzing the transfer of ATP to specific tyrosine residues in target proteins. In turn, the phosphorylation of tyrosine residues causes a change in the function of the protein that they are contained in. They function in a variety of processes, signal transduction pathways, and actions, and may be responsible for key events in the body[1]. Axon Ligands™ that interact with tyrosine specific enzymes that are part of the JAK/STAT signaling pathway have been categorized independently. The remainder of Axon Ligands™ that lack interactions with tyrosine kinases of this particular signaling pathway are listed here, grouped on the basis of their selectivity.