Six-seven private equity firms and strategics, including Blackstone Inc. (NYSE:BX) and KKR & Co. Inc. (NYSE:KKR), are understood to have submitted non-binding bids to acquire Bharat Serums and Vaccines Limited from Advent International, L.P. in a deal valued at over $2 billion, sources said. Bids were to be submitted by the end of May.

Others who have shown interest include The Carlyle Group Inc. (NasdaqGS:CG), Bain Capital, LP, and the UK's Permira (Permira Advisers Ltd.), while pharma and healthcare products company Mankind Pharma Limited (NSEI:MANKIND) is also reportedly interested. Blackstone had no comment to offer, KKR did not respond by press time, and Advent declined comment.