Acts on tyrosine phosphorylated proteins, low-MW aryl phosphates and natural and synthetic acyl phosphates with differences in substrate specificity between isoform 1 and isoform 2. H2O + O-phospho-L-tyrosyl-[protein] = L-tyrosyl-[protein] + phosphate a phosphate monoester + H2O = an alcohol + phosphate Inhibited by sulfhydryl reagents. Interacts with EPHA2; dephosphorylates EPHA2. Interacts with EPHB1. Interacts with the SH3 domain of SPTAN1. There is no interaction observed for isoform 2. Widely expressed with highest levels in brain and liver and lowest levels in muscle. Phosphorylated by LCK. Phosphorylation at Tyr-132 increases its phosphatase activity. Belongs to the low molecular weight phosphotyrosine protein phosphatase family.