Dual-specificity phosphatase. Preferentially dephosphorylates proteins modified by proline-directed kinases (By similarity). H2O + O-phospho-L-tyrosyl-[protein] = L-tyrosyl-[protein] + phosphate H2O + O-phospho-L-seryl-[protein] = L-seryl-[protein] + phosphate H2O + O-phospho-L-threonyl-[protein] = L-threonyl-[protein] + phosphate Retains its endoplasmic reticulum localization during mitosis. Composed of two structurally equivalent A and B domains that adopt a dual specificity protein phosphatase (DSP) fold. May act as an autosomal functional substitute. Belongs to the protein-tyrosine phosphatase family. Non-receptor class CDC14 subfamily. Extended N-terminus.