US copper reserves expand sharply, tightening global supply and pushing prices higher

American refined-copper inventories have increased markedly over the past year, removing material volumes from normal export channels and reshaping global trade flows. That concentrated holding has coincided with a broader rally: London Metal Exchange prices have pushed to new highs as exchange stockpiles have been drawn lower and physical premiums in some regions widened. Together, the US accumulation and exchange draws have tightened immediate availability, prompting thinner offers, longer lead times and elevated premiums for prompt delivery. Traders and fabricators report that metal that would normally circulate through global distribution networks is increasingly locked in US warehouses, compressing exportable supply. The price response has been amplified by speculative flows and currency moves that pushed more capital into commodity derivatives, compounding raw-material tightness. Miners and intermediaries have benefited from firmer quotations and improved margins, while also confronting constraints on the pace of new supply given permitting delays and rising project costs. Downstream manufacturers — notably in electrical, industrial and clean-energy supply chains — are facing higher input-cost risk and are accelerating plans for substitution, recycling and alternative sourcing. Commodity intermediaries are re-routing shipments and rebalancing inventories to reduce exposure to concentrated US holdings and regional delivery pressures. Policymakers and industry stakeholders are monitoring whether the stock accumulation reflects temporary commercial positioning or a strategic, longer-term buffer; the path will dictate whether price pressure persists or reverses. A rapid unwind of the enlarged US stockpile would pose the opposite risk—heavy downward pressure that could strand hedges and disrupt producer revenue expectations. Market participants should stress-test scenarios that include both a slow release and a sudden liquidation of US holdings, and watch exchange inventories, regional premium spreads and capital-spending signals from major producers as the clearest near-term indicators of whether the squeeze is transient or structural.