Catalysis of the reaction: 1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate + H2O = 1-phosphatidyl-1D-myo-inositol 3-phosphate + phosphate.
1-phosphatidyl-1D-myo-inositol-4,5-bisphosphate 4-phosphohydrolase activity