What is Anti-Dumping?

Dumping is a process where a company exports a product at a price lower than the price it normally charges on its own home market. To protect local businesses and markets, many countries impose stiff duties on products they believe are being dumped in their national market.
The World Trade Organization (WTO) operates a set of international trade rules. Part of the organization's mandate is the international regulation of anti-dumping measures. The WTO does not regulate the actions of companies engaged in dumping. Instead, it focuses on how governments can or cannot react to dumping. In general, the WTO agreement allows governments to "act against dumping where there is genuine (material) injury to the competing domestic industry." In other cases, the WTO intervenes to prevent anti-dumping measures. This intervention is justified to uphold the WTO's free market principles. Anti-dumping duties distort the market. Governments cannot normally determine what constitutes a fair market price for any good or service; fair market value is whatever price the market will bear as determined by supply and demand.
Practical Examples of Anti-Dumping Measures - In June 2015, American steel companies United States Steel Corp., Nucor Corp., Steel Dynamics Inc., Arcelor Mittal USA, AK Steel Corp. and California Steel Industries filed a complaint with the Department of Commerce and the ITC alleging that China (and other countries) were dumping steel on the U.S. market and keeping prices unfairly low.

A year later, the United States, after a review and much public debate, announced that it would be imposing a 500% import duty on certain steel imported from China. China may bring the debate before the WTO by China if it feels the tariffs are unfair.