A consortium led by former boss David Gao has filed an all-cash $3.9 billion offer for Nasdaq-listed China Biologic Products, topping an existing bid by Citic Capital Holdings as the battle to take the plasma treatment provider private heats up anew.
Former chief executive and chairman Gao, who led the company for six years before stepping down after Citic's $3.6 billion offer in June, is backed by...