Quantinuum Inc., the quantum‑computing spin‑out backed by Honeywell International, closed its U.S. IPO on Thursday, raising $1.68 billion. The offering was upsized beyond the originally filed amount, reflecting strong demand significantly from both institutional and retail investors. By securing more than a billion dollars, the firm joins a short list of quantum players that have accessed public markets.

Investors see Quantinuum as a gateway to practical quantum advantage, betting that the company’s hardware and software stack can eventually serve sectors ranging from pharmaceuticals to finance. The IPO proceeds will fund expanding the chip production line, hiring additional engineers, and scaling cloud‑based quantum services. Market observers note that the capital raise signals confidence in the commercial timeline for quantum technologies.

The successful float gives Honeywell a publicly traded partner that can accelerate its own quantum roadmap, while providing Quantinuum with a liquid valuation benchmark. Wall Street analysts will now compare the company’s market cap against peers such as IBM and Google’s quantum arms, shaping future merger or partnership talks. For now, the deal underscores that capital markets are willing to back high‑risk, long‑term computing bets.