An extremely versatile pigment dispersant for acrylic, acrylic-styrene, and vinyl acrylic based coatings. This sodium salt of a maleic anhydride copolymer is very effective as a general dispersant in coatings applications. It offers good gloss and hiding at economical use levels. In addition, when formulated with a high-performance binder and other high-quality additives, it can offer excellent corrosion resistance to coatings formulations.