China won the bulk of a World Trade Organization complaint against certain US methods of determining anti-dumping duties on Chinese products in a WTO dispute panel ruling released on Wednesday, Reuters reports. China brought the complaint in December 2013, one of a string of disputes challenging Washington’s way of assessing “dumping.” Specifically, the panel found fault with the US practices of determining dumping margins in certain cases of “targeted dumping,” in which foreign firms cut prices on goods aimed at specific US regions, customer groups or time periods. The panel ruled against the US Commerce Department’s practice of “zeroing” in cases involving targeted dumping. In zeroing, the department typically assigns a value of zero any time a producer’s export price is above that producer’s normal home market price.