Staff workers check a photovoltaic product at a solar energy company in Hangzhou, capital of east China's Zhejiang Province, May 24, 2012. European Commission filed an antidumping investigation over Chinese photovoltaic (PV) products Thursday. The case is the largest trade dispute involving China in terms of trade volume, as the country's solar product exports were valued at 35.8 billion U.S. dollars in 2011, with the EU receiving a share of more than 60 percent, or 20.4 billion U.S. dollars. [Xinhua]