Has phosphatase activity toward PtdIns(4,5)P2, PtdIns(3,4,5)P3 and Ins(1,4,5)P3. a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol-4,5-bisphosphate) + H2O = a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol 4-phosphate) + phosphate a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol-3,4,5-trisphosphate) + H2O = a 1,2-diacyl-sn-glycero-3-phospho-(1D-myo-inositol-3,4-bisphosphate) + phosphate 1D-myo-inositol 1,4,5-trisphosphate + H2O = 1D-myo-inositol 1,4-bisphosphate + phosphate A number of isoforms are produced. According to EST sequences. Expressed in young seedlings and flowers. Slightly reduced by dark treatment. Belongs to the inositol polyphosphate 5-phosphatase family.