In an era when artificial intelligence infrastructure has become as consequential as roads and power grids, the Justice Department has turned its gaze toward Nvidia — the company whose chips undergird much of the world's AI ambition. At issue is a licensing agreement between Nvidia and Groq, an AI chip startup, which federal regulators are now examining for signs that market dominance may be quietly encoded into commercial terms. The investigation reflects a recurring tension in technological history: when a single company becomes indispensable, the question of how it shares — or withholds — a