This bill allows commercial mobile service providers to voluntarily transmit emergency alerts to their subscribers via satellite, supplementing existing alert systems. Providers choosing this option must notify the Federal Communications Commission (FCC) and comply with technical standards, while those opting out must inform their subscribers. Subscribers can still opt out of receiving these satellite alerts, and providers are expressly forbidden from charging any additional fees for this capability. The FCC is tasked with issuing a final rule within 18 months to establish requirements for this satellite alerting capability, considering both satellite and mobile device functionality and minimizing impact on other communications. The rule's effective date depends on its publication and the implementation of supporting standards by the Department of Homeland Security and FEMA. Additionally, the bill includes liability limitations for providers transmitting alerts by satellite, protecting them from claims related to transmission or failure, and clarifies that not electing to transmit alerts by satellite does not, by itself, create liability.