Health sector trade union brings suit saying Fonterra had been misleading the public with its advertising.
New Zealand-based dairy giant disputes accuracy of testing that led to authorities ordering withdrawal.
Three companies pay penalties including Mead Johnson Nutrition and dairy giant Fonterra.
World's largest dairy exporter under fire from New Zealand government, farmers and regulators.
Says processing methods would kill off harmful bacteria, and problem will be resolved within two days.
Food safety concerns that threatens $9.4 billion annual dairy trade.
Prompts China to issue a recall of affected products; New Zealand holds back some widely used infant formula products from supermarket shelves.
World's largest dairy producer joins a growing list of firms responding to Beijing's investigation into the sector.
Asian markets followed Wall Street higher on Wednesday after upbeat economic data from the world's largest economy.
