SpaceX has entered into an agreement to acquire a nationwide low-band spectrum portfolio from the private-equity firm Grain Management. The financial terms of this transaction remain undisclosed. Following the announcement, shares of major US mobile carriers Verizon, AT&T, and T-Mobile dropped by approximately 6% in after-hours trading.

The acquired assets consist of up to 14 MHz of paired spectrum within the 800 MHz band. This acquisition is intended to enhance the capabilities of Starlink Mobile, the company's satellite-to-phone service. Unlike the 2 GHz mid-band frequencies previously utilized by the service, low-band spectrum offers superior range and indoor penetration, allowing signals to bypass obstacles like buildings and foliage.

Grain Management had previously acquired these specific airwaves from T-Mobile on August 11 for $2.9 billion in cash and 600 MHz licenses. The Federal Communications Commission approved the original swap on July 1. SpaceX's move comes as the company also secured regulatory approval from the FCC for a 15,000-satellite Starlink Mobile Gen2 constellation.

Market reaction to the deal was mixed, with SpaceX shares rising nearly 3% during the same session. In contrast, AT&T saw the steepest decline among carriers, falling nearly 7%, while Verizon and T-Mobile shares dropped by more than 6% and 6% respectively. Major carriers have invested approximately $110 billion over the past decade to secure the majority of US low-band spectrum.