TeraWulf announced a 20-year power and infrastructure lease with Anthropic worth $19 billion in aggregate revenues, the largest customer contract in the company's history and a structural pivot from its Bitcoin-mining roots. The stock moved 28% intraday before settling 19% higher at the close.

The agreement commits Anthropic to 950 million kilowatt-hours annually beginning in late 2026, with TeraWulf delivering capacity from its Lake Mariner facility in upstate New York. Anthropic pays a blended rate of roughly $0.10 per kWh, materially above the $0.04-$0.06 spot power costs TeraWulf pays its utility providers, locking in a 40-60% gross margin on power resale alone before factoring infrastructure fees. The contract includes annual escalators tied to CPI with a 2% floor, ensuring revenue grows faster than inflation even in deflationary scenarios.

This matters because TeraWulf spent the last 18 months repositioning from a pure-play Bitcoin miner into a hybrid data-center operator, a transition most legacy miners attempted and few completed credibly. The Anthropic lease validates the pivot and gives TeraWulf a creditworthy counterparty at a time when AI labs are competing for scarce power-adjacent real estate near low-latency fiber. Anthropic's parent investor base—Menlo Ventures, Spark Capital, and a $4 billion commitment from Amazon—means the contract carries enterprise-grade counterparty risk, a material upgrade from the revenue volatility of Bitcoin mining. The deal also front-runs a broader trend: hyperscalers and AI labs increasingly lease long-term power rather than build greenfield data centers, compressing time-to-deployment from 4-5 years to 18-24 months.

The revenue structure is predictable and non-recourse. TeraWulf receives a fixed annual payment of roughly $950 million starting in 2027, with no exposure to Anthropic's model performance, customer growth, or fundraising cycles. The company's legacy Bitcoin operations contributed $87 million in revenue over the last twelve months, meaning the Anthropic contract will represent roughly 91% of total revenues once operational. That concentration is a feature, not a bug—Anthropic's contract length and creditworthiness allow TeraWulf to raise project-level debt at 200-250 basis points below what a pure-play crypto miner could access, and the revenue visibility supports a dividend or buyback program starting in 2028.

Operators should track TeraWulf's ability to replicate this model at its other facilities, particularly the 300 MW site under development in Pennsylvania, where construction timelines and utility interconnection agreements will determine whether the company can sign a second hyperscale lease before mid-2026. Watch Anthropic's deployment pace—if the lab begins drawing power earlier than the contracted late-2026 start, TeraWulf will recognize revenue ahead of consensus and potentially trigger early-payment clauses worth an additional $200-$300 million. The company reports Q4 earnings in early March; guidance on capital expenditures for the Lake Mariner buildout will clarify whether TeraWulf can self-fund the infrastructure or needs to raise equity at dilutive terms.

TeraWulf now holds the largest publicly disclosed AI power lease by a non-utility, signed 14 months before the first kilowatt-hour is delivered.