APlus is an American convenience store chain owned & operated by Sunoco, Inc.The chain began life as the convenience store chain for Atlantic Petroleum in 1985, which was spun off from ARCO, Inc. (ARCO itself was formed from the 1966 merger of Atlantic and Richfield Oil.) The first Aplus stores were rebranded ampm locations.In 1988, Sunoco bought Atlantic, and since Sunoco didn't have its own convenience store chain, APlus became Sunoco's chain by default.