Generic drug firms Teva Pharmaceutical and Mylan keep upping the ante in a clash of hostile takeover bids but have gotten no closer to ending their impasse. Last week, Mylan rejected Teva’s $40 billion offer as too low and too risky because of stock value and antitrust issues. A merger “would expose Mylan to a problematic culture and leadership with a poor record of delivering shareholder value,” Mylan’s board maintains. Combining the number-one- and -four-ranked generic drug suppliers would also result in “massive consolidation of supply and manufacturing, creating implications for pricing power and shortages,” it added. Meanwhile, Mylan has made three offers to buy Perrigo, the most recent at nearly $36 billion. Perrigo has rejected all of them as undervaluing the company. With Mylan making aggressive moves on Perrigo, Teva will likely have to increase its offer price to win over Mylan. Teva faces a “long, drawn-out battle” that could last several months, says Evercore ISI stock analyst Umer Raffat, who doesn’t expect Teva to go much more than 10% higher.