A non-specific tyrosine phosphatase that dephosphorylates a diverse number of substrates under acidic conditions (pH 4-6) including alkyl, aryl, and acyl orthophosphate monoesters and phosphorylated proteins. Has lipid phosphatase activity and inactivates lysophosphatidic acid in seminal plasma (By similarity). In addition to its tyrosine phosphatase activity, also has ecto-5'-nucleotidase activity in dorsal root ganglion (DRG) neurons. Generates adenosine from AMP. This extracellular adenosine leads to a decrease in chronic pain by activating A1R in nociceptive neurons. a phosphate monoester + H2O = an alcohol + phosphate a ribonucleoside 5'-phosphate + H2O = a ribonucleoside + phosphate 1-(9Z-octadecenoyl)-sn-glycero-3-phosphate + H2O = 1-(9Z-octadecenoyl)-sn-glycerol + phosphate H2O + O-phospho-L-tyrosyl-[protein] = L-tyrosyl-[protein] + phosphate Homodimer; dimer formation is required for phosphatase activity. Appears to shuttle between the cell membrane and intracellular vesicles. Colocalizes with FLOT1 at cell membrane and in intracellular vesicles (PubMed:17638863). Colocalizes with LAMP2 on the lysosome membrane (By similarity). Expressed in salivary gland, thymus and thyroid gland. Widely expressed in prostate lobes, brain, kidney, liver, lung, muscle, placenta, salivary gland, spleen, thyroid and thymus. Locates to Schwann cells and fibroblasts. Expressed in peptidergic and non-peptidergic nociceptive (pain-sensing) neurons. Preferentially expressed in non-peptidergic doral root ganglia neurons. Null mice display greater thermal hyperalgesia (pain sensitivity) and mechanical allodynia. No thiamine monophosphatase (TMPase) activity detected in dorsal root ganglion (DRG) neurons. Belongs to the histidine acid phosphatase family.