"We have received a copy of the lawsuit filed gainst the generic drug manufacturers and are reviewing details of the same," Lupin Ltd said in a regulatory filing.
"The company has been a key pharmaceutical player in the US and has demonstrated full commitment to compliance with all laws and ethical business practices," it added.
The Mumbai-based drug firm along with various other domestic companies like Sun Pharma, Dr Reddy's Laboratories and Wockhardt are among the 21 generic pharmaceutical firms and 15 other individual defendants against whom the Attorneys General of 49 US states, the Commonwealth of Puerto Rico and the District of Columbia had filed a complaint with respect to 116 generic drugs in the US District Court for the District of Connecticut.
The companies have been accused of violating antitrust laws by fixing prices and allocating customers.
Lupin shares were trading 3.66 per cent down at Rs 779.50 apiece on the BSE.