A cocktail of three inhibitors that will inhibit alkaline phosphatases as well as serine/threonine protein phosphatases such as PP1 and PP2A. This product is provided as a set of five 1 ml vials. Each vial contains 1 ml phosphatase inhibitor cocktail solubilized in DMSO with the following components: Bromotetramisole oxalate (2.5 mM), Cantharidin (Cat. No. 210155; 500 µM), and Microcystin-LR (Cat. No. 475815; 500 nM).