Crown Castle Inc. owns or manages approximately 40,000 wireless towers across the United States. The company generates revenue by leasing tower space to wireless carriers, which install network equipment to support mobile service coverage and capacity. Its customer base is highly concentrated, with roughly 90% of revenue coming from the three largest U.S. mobile operators: Verizon, T-Mobile, and AT&T. Crown Castle also plans to divest its fiber business, a transaction expected to close in the first half of 2026. Following that divestiture, the company is expected to operate as a pure-play tower business. Crown Castle is structured as a real estate investment trust.