On December 27, 2024,  the National Telecommunications and Information Administration (NTIA) issued a Request for Comment (“RFC”)that seeks public input on the potential impacts on the Global Positioning Satellite (GPS) L1 signal by the growth of satellite-based direct-to-device (D2D) operations that use frequencies between 1610-1660.5 MHz (the “L-band”).   As the lead spectrum advisor to the Executive Branch on spectrum issues, NTIA serves as the advocate for other agencies including the Department of Transportation (DOT) before the FCC.  NTIA issued its Request for Comment (RFC) in response to analysis prepared by DOT and states that its interest in D2D usage stems from the increasing deployment of services in which mobile devices like smartphones and Internet of Things (IoT) devices connect directly to satellite systems in the L-band, a portion of which is located near spectrum allocated to GPS.  NTIA invited comments to be filed by February 10, 2025.