Acts as a phosphoinositide 5- and phosphoinositide 6-phosphatase and regulates cellular levels of inositol pentakisphosphate (InsP5) and inositol hexakisphosphate (InsP6) (PubMed:9472008). Also acts as a 2,3-bisphosphoglycerate 3-phosphatase, by mediating the dephosphorylation of 2,3-bisphosphoglycerate (2,3-BPG) to produce phospho-D-glycerate without formation of 3-phosphoglycerate (By similarity). May play a role in bone development (endochondral ossification) (By similarity). May play a role in the transition of chondrocytes from proliferation to hypertrophy (PubMed:8660956, PubMed:9472008). myo-inositol hexakisphosphate + H2O = myo-inositol pentakisphosphate (mixed isomers) + phosphate. (2R)-2,3-bisphosphoglycerate + H2O = (2R)-2-phosphoglycerate + phosphate Optimum pH is 4.5-7.5. Present in growth plate chondrocytes but not detectable in articular chondrocytes (at protein level) (PubMed:9472008). Spatially restricted to chondrocytes in the lower portion of the proliferative zone and the upper portion of the hypertrophic zone in the growth plate of long bones (at protein level) (PubMed:9472008). Weakly expressed in kidney, liver, lung, skin and spleen, and not detected in brain, heart and muscle (PubMed:8660956). Repressed by parathyroid hormone-related protein PTHLH/PTHRP. N-glycosylated. Monogastric animals cannot hydrolyze dietary inositol hexakisphosphate (InsP6) which makes up the bulk of organic phosphates in soybean, grains and other plant seeds which are the primary source of animal feed. The high activity of the chicken protein toward InsP6 offers a genetic strategy for improving InsP6 digestion in poultry and reducing the pollution that results from high phosphate content in manure. Belongs to the histidine acid phosphatase family. MINPP1 subfamily.