Biotechnology Following a day of speculation and rumor on Friday, US biotech firm Onyx Pharmaceuticals (Nasdaq: ONXX) on Sunday issued a statement confirming it has received and rejected an unsolicited proposal from Amgen (Nasdaq: AMGN), the world's largest independent biotech group, to acquire all of Onyx's outstanding shares and share equivalents for $120 per share in cash, a premium of some 38% to its most-recent closing price, or around $10 billion in total. 1 July 2013