U.S. Steel Acquisition Unleashes the Power of "X" on NYSE

By Grace Turner Jun 22, 2025

Untangling the curiosity behind the now-available single-letter stock symbol "X", post the merger of U.S. Steel and Nippon Steel.

With U.S. Steel's acquisition by Nippon Steel confirmed, a previously obscure detail surfaces; who will claim the company's unique New York Stock Exchange (NYSE) single-letter stock symbol "X"? This merger, endorsed by President Donald Trump and characterized by a "golden share" granting the U.S. government specific rights over the company's future, not only signifies a notable shift in the steel industry but also leaves the "X" open for picking after several decades.

On the NYSE, only six single-letter stock symbols remain unoccupied; "X" joins the unused ranks of "I", "N", "P", "Q", and "Y". These symbols offer distinct brand recognition among the bustling sea of company abbreviations on the stock exchange, with well-known names like Citigroup ("C"), Ford ("F"), and Macy's ("M") sporting single-letter monikers.

For a company to claim the "X", a formal application supported by a justifiable intent for its use within 24 months must be submitted to the NYSE. The stock exchange observes a mandatory "cooling off" period of a minimum 90 days post the release of any symbol to prevent confusion.

Potential contenders for the coveted "X" kingdom may include Elon Musk's artificial intelligence firm xAI or his space exploration venture SpaceX. However, neither have indicated intentions to sell their shares anytime soon, and requests for comment remained unanswered. As it stands at present, the entity that will ultimately seize the "X" remains a mystery, only adding to the thick of uncertainties following the significant merger.

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