Shares of Ranbaxy Laboratories today slumped over 9 per cent in the morning trade, after its Japanese promoters blamed the company’s former Indian owners for concealing and misrepresenting critical information about US investigation into the sale of adulterated drugs.

Following the news, the scrip opened the day on a weak note and further tanked 9.3 per cent to Rs 391 on the BSE. On the NSE, the stock tumbled 9.37 per cent to Rs 390.65.

At 2.10 p.m., the scrip was trading down by 9.3 per cent at Rs 391 on the BSE and down by 9.35 per cent at Rs 390.75 on the NSE.

Following the weakness in the stock, the market value of the company slipped by Rs 1,527 crore to Rs 16,708 crore.

Ranbaxy’s Japanese promoters had yesterday blamed the company’s former Indian owners for concealing and misrepresenting critical information about US investigation into the sale of adulterated drugs, and said it will pursue legal remedies.

“Daiichi Sankyo believes that certain former shareholders of Ranbaxy concealed and misrepresented critical information concerning the US Department of Justice and FDA investigations. Daiichi Sankyo is currently pursuing its available legal remedies,” Daiichi Sankyo had said in a statement.

The Japanese drug maker added that it continued to support Ranbaxy in its efforts to address and correct the conduct of the past which led to the investigations.

Ranbaxy became a part of the Daiichi Sankyo Group in 2008 after Japan’s third largest drug maker bought a majority stake in the Indian firm. Daiichi had bought 34.82 per cent stake in the Gurgaon-based firm from its promoters, Malvinder Singh and family.

Last week, pleading guilty to “felony charges” relating to manufacture and distribution of certain adulterated drugs made at two India units, the US subsidiary of Ranbaxy had agreed to pay $500 million in settlement with the US authorities.