Pfizer Inc offered $90 per share in cash, a 39 per cent premium to Hospira's closing stock price on Wednesday. Hospira soared 35% to near $88 before the bell Thursday, while Pfizer was up 3.6%.
For Pfizer, the deal is the largest since its failed takeover attempt of AstraZeneca Plc, which rebuffed its $118 billion approach last year but has remained a subject of takeover speculation.
The stock opened at Rs 2,005, touched a high of Rs 2,082 on the BSE. A total of 21,000 shares changed hands on both the counters so far.