Novo Nordisk submitted an unsolicited, superior proposal to buy obesity biotech Metsera, challenging Pfizer’s previously announced acquisition and igniting a cross‑border bidding war. Novo’s offer layers cash up front with contingent value rights tied to clinical and regulatory milestones; Metsera’s board has deemed the proposal a “Superior Company Proposal” and asked Pfizer for four business days to respond. Pfizer publicly rejected Novo’s approach, calling the bid “reckless and unprecedented” and accusing Novo of trying to suppress competition and structure the deal to skirt U.S. antitrust constraints. Metsera’s pipeline—led by an investigational monthly GLP‑1 candidate and an amylin analog—has made the company a coveted asset as big pharma races to secure obesity franchises. The dispute spotlights the white‑hot obesity market: strategic buyers are offering large premiums and contingent payments tied to clinical success, while regulators and rival bidders monitor whether aggressive deal tactics will trigger legal or antitrust pushback.