Novo Nordisk unveiled an unsolicited up-to-$9 billion proposal for obesity biotech Metsera, signaling a sudden escalation in a deal Pfizer had previously agreed to buy. Metsera’s board characterized Novo’s two-step offer—$56.50 per share upfront plus contingent value rights worth up to $21.25 per share—as a “superior company proposal,” triggering a four-business-day window for Pfizer to respond. Pfizer swiftly condemned the move as “reckless and unprecedented,” arguing Novo’s structure creates regulatory and execution risks and may be aimed at suppressing competition. The spat highlights the strategic value of Metsera’s pipeline—monthly GLP-1 candidate MET‑097i, an amylin analogue MET‑233i and combination approaches—and underscores intensifying consolidation in the obesity drug market, where scale and portfolio breadth determine competitive positioning. For dealmakers and drug developers, the contest matters because it could reshape M&A norms in a sector where pricing power, commercialization reach, and next‑generation incretin assets are core strategic assets. Antitrust scrutiny and cross-border regulatory risk are now central variables for any suitor.