Ranbaxy Laboratories [Get Quote] on Monday said the Japanese drug maker Daiichi Sankyo's open offer for acquiring an additional 20 per cent stake in the domestic pharma firm has been fully subscribed.

In response to the offer, the number of shares tendered by the shareholders exceeded the offer size of 9.25 crore shares, representing 20 per cent of the voting capital of Ranbaxy, domestic pharma major said in a filing to the Bombay Stock Exchange.

Earlier in June, Daiichi had agreed to acquire the promoters' 34.8 per cent stake in Ranbaxy, pursuant to which it made an open offer for acquiring up to 9.25 crore shares at a price of Rs 737 each.

Following the promoter stake buy-out, the Japanese drug major on August 16 launched an open offer to acquire up to 9,25,19,126 shares, representing a further 20 per cent stake in Ranbaxy.

Indian takeover regulations necessitates an acquirer to make an open offer for an additional 20 per cent stake in the target firm if its holding reaches 15 per cent.

After completion of the offer, Daiichi now holds over 58.09 per cent stake in Ranbaxy. ICICI [Get Quote] Securities acted as the manager to the offer.

Daiichi had announced the acquisition for a majority stake of more than 50 per cent in Ranbaxy for over Rs 15,000 crore (Rs 150 billion). The acquisition is expected to complete by March 2009.

In June, Daiichi Sankyo had announced the acquisition of a majority stake of more than 50 per cent in Ranbaxy, making it the largest ever deal in the Indian pharma industry.