The 63 defendants in the first-known group lawsuit stemming from the scandal, including the parents of two children who died, were seeking nearly 14 million yuan ($2 million) in compensation from state-owned Sanlu Group Co., Beijing-based lawyer Xu Zhiyong said.

The dairy based in the northern Chinese city of Shijiazhuang was at the center of China's worst food safety crisis in years, in which six babies are believed to have died and nearly 300,000 became sick with urinary problems after drinking infant formula tainted with the industrial chemical melamine.

Three of six defense lawyers presented the suit to the Hebei Supreme Court's registry office on Monday but were told it could not be accepted because government departments were still investigating.