Array Digital Infrastructure is a U.S. tower company that owns and leases space on approximately 4,450 cell towers across 19 states, concentrated in suburban and rural markets. Array completed a transformative transaction in August 2025, selling its legacy wireless operations to T-Mobile for approximately $4.3B, leaving Array as a pure-play tower company. Array's core business is leasing vertical space on its towers to wireless carriers — T-Mobile, AT&T, and Verizon — under long-term Master License Agreements with contractual annual rent escalators. The central economic driver is tenancy rate: adding more tenants to a tower generates revenue at very high incremental margins, since tower fixed costs are largely unchanged. Array's current tenancy rate is low relative to peers, as the portfolio was historically built to serve UScellular's own network — a near-term challenge but a long-term lease-up opportunity. Beyond tower operations, Array holds passive minority stakes in wireless partnerships managed by AT&T and Verizon, which generate recurring distributions, and retains wireless spectrum licenses being monetized through separate sale agreements. Array's growth strategy focuses on executing the T-Mobile MLA (which commits T-Mobile to at least 2,015 colocation sites over 15 years), driving colocation growth with AT&T and Verizon, and optimizing its ground lease cost structure. Array's parent, TDS, also operates TDS Telecom, a separate fiber broadband business targeting 2.1M fiber service addresses by approximately 2029–2030.