May be involved in assembly or function of the EPS I polymerization/export complex and/or the EpsB ATPase. Alternatively it may function in the removal of the terminal phosphate from C55-isoprenyl pyrophosphate in order to recycle the C55-isoprenyl phosphate lipid carrier used in the synthesis of polysaccharide repeat units. H2O + O-phospho-L-tyrosyl-[protein] = L-tyrosyl-[protein] + phosphate Glycan metabolism; exopolysaccharide biosynthesis. Belongs to the low molecular weight phosphotyrosine protein phosphatase family.