SH2-containing inositol phosphatase (SHIP) is a 145 kDa hematopoietic-restricted protein that becomes tyrosine-phosphorylated and associated with the adaptor protein, Shc, following cytokine, growth factor, chemokine, and immunoreceptor stimulation. SHIP also hydrolyzes the critical phosphatidylinositol (PI)-3-kinase (PI3K)-generated second messenger, PI-3,4,5-P3 (PIP3), to PI-3,4-P2 1,2 and therefore acts as an important negative regulator of the PI3K pathway. This antibody reacts with mouse full-length SHIP protein, 145 kDa, as well as the C-terminal truncated 135, 125, and 110 kDa forms.