Abstract: This paper examines the tariff-jumping response of all firm and product combinations subject to US antidumping investigations from 1980 to 1990 using a newly constructed database. Previous studies have focused only on Japanese FDI responses to antidumping protection and found large tariff-jumping responses. In contrast, this paper finds quite modest tariff-jumping responses and the evidence suggests that tariff-jumping is only a realistic option for multinational firms from industrialized countries. This may partially explain developing countries' concerns about addressing AD protection in the WTO. Despite high tariff-jumping responses, there is no evidence of a Japanese-specific propensity to tariff-jump, holding other economic factors constant.