In two lawsuits, filed in 1996, two Chinese plaintiffs sued Japan for leaving leaking chemical weapons in China after WWII.
From People's Daily:
The Tokyo High Court on Wednesday rejected the demands by Chinese plaintiffs seeking compensation from the Japanese government for their sufferings caused by chemical weapons left behind by the Imperial Japanese Army in China at the end of World War II.
The high court overturned an earlier ruling by the Tokyo District Court in September 2003, which ruled that the Japanese government should pay a total of 190 million yen (1.56 million U.S. dollars) to 13 Chinese victims or families of victims. [Full Text]