Phosphatase that has a high activity toward phosphoethanolamine (PEA) and phosphocholine (PCho) (By similarity). Involved in the generation of inorganic phosphate for bone mineralization (PubMed:15050893). H2O + phosphoethanolamine = ethanolamine + phosphate H2O + phosphocholine = choline + phosphate Localizes to special class of extracellular vesicles, named matrix vesicles (MVs), which are released by osteogenic cells. Expressed at sites of mineralization in bone and cartilage. Highly expressed in hypertrophic chondrocytes compared to non-chondrogenic tissues. Expressed in chondrocytes but not in heart, liver, lung, kidney, spleen, muscle, adipose tissues not duodenum. In diaphyseal cortical bone, it is expressed in the osteoid layer of the periosteum, forming surfaces of growing osteons, and newly formed osteocytes, whereas it is not expressed in the endosteum and closed osteons. In growth plate cartilage, it is limited to the early hypertrophic chondrocytes and the ossification groove of Ranvier. Highly expressed on the mineralization surfaces of the cartilage remnants and trabecular bone within the primary spongiosa. Expressed in 17-day-old embryonic calvaria, the osteoid present on the intramembranous and periosteal bone surfaces but not in soft tissues examined. Up-regulated 5-fold during chondrocyte terminal differentiation. Belongs to the HAD-like hydrolase superfamily. PHOSPHO family.