Novo Nordisk launched a surprise unsolicited bid for Metsera that outvalues Pfizer’s previously agreed acquisition, setting off a rapid escalation in the obesity M&A sweepstakes. Novo offered roughly $6.5 billion upfront plus contingent value rights that lift the proposal to about $9 billion, prompting Metsera’s board to call the offer “superior” and giving Pfizer four business days to respond. Pfizer publicly criticized the bid and signaled legal and regulatory pushback, calling Novo’s move “reckless and unprecedented,” arguing it could suppress competition and skirt antitrust risks. The episode underscores intense strategic jockeying among big pharmas for next‑generation obesity assets as market leaders defend and expand lucrative metabolic franchises.