Copper is surging toward a record on the London Metal Exchange, and the market’s warning lights are flashing brighter by the hour. Three-month futures climbed as much as 1.7% to $14,396 a tonne on Aug. 17, while the prompt spread blew out to an extreme $543.50 a tonne backwardation, the widest gap since the 2021 squeeze. The move reflects a scramble for nearby supply at a moment when inventories are thinning and traders are waiting for the next policy shock out of Washington.
What makes this rally harder to dismiss is the shape of the market, not just the price. Copper was trading at $14,334 a tonne at 3:06 p.m. Singapore time, still up 1.2% on the day, after already gaining almost 16% year to date. In a market this tight, the front end matters more than the headline level. When prompt contracts trade at a huge premium to later delivery, it tells you buyers are willing to pay up now rather than wait.
The supply squeeze is visible in the warehouse data. LME-tracked inventories have shrunk to just above 200,000 tonnes, the lowest since February. That matters because the exchange network is the benchmark for freely deliverable metal in the financial market, and shrinking stocks leave less buffer for shorts to source metal into delivery. At the same time, global inventories are not especially low overall. They are simply sitting in the US, outside the LME system, which helps explain why the London market can look stressed even if the broader world is not running dry.
David Wilson, head of metals strategy at BNP Paribas SA, said the market still has momentum. “There seems to be momentum for it to get there… It’s moving into overbought territory but I don’t know if that means anything at the moment, given how tight it is.” In other words, the usual technical warning signs are getting louder, but tight physical conditions are overpowering them for now. That is often how commodity squeezes feed on themselves: price strength attracts more attention, which can tighten prompt availability further.
The cash-to-three-month spread is the market’s loudest alarm. An extreme backwardation means traders will pay more for immediate copper than for metal a few months out, a sign that available units for near-term delivery are scarce. The intraday peak of $543.50 a tonne marks the widest gap since the 2021 squeeze, putting London back into a pattern that traders know can force fast, disorderly repositioning. For shorts, the cost of waiting rises when the front month keeps outperforming the back end.
The timing is also awkward. The latest moves come shortly ahead of the third-Wednesday delivery date, the main liquidity focus for LME contracts. That date can act like a pressure point because positions tied to near-term delivery have to be resolved, rolled, or covered. In a market already showing signs of stress, that can amplify volatility rather than calm it. The tighter the prompt market, the less room traders have to sit still and hope the spread normalizes on its own.
One reason London supply is tight is that metal has been flowing into the US ahead of a potential Trump administration tariff decision. That shift has helped push copper almost 16% higher this year. The result is a distorted global setup: the physical metal is not necessarily disappearing, but it is moving to a different jurisdiction, leaving the LME system with less available stock and more pressure on nearby contracts. The market is effectively pricing not just copper demand, but location, logistics and policy risk.
No tariff announcement has emerged about seven weeks after the Commerce Department’s recommendation deadline. That delay leaves the market in an uncomfortable holding pattern. Traders know a decision is still possible, but they do not know when it will land or how severe it will be. Uncertainty itself can be bullish when physical supply is already tight, because buyers rush to secure material before a policy shift changes the economics again. The longer the wait continues, the more this becomes a story about positioning as much as fundamentals.
For now, the key question is whether the market can keep stretching without a bigger reset. Copper has already pushed into overbought territory by some measures, but that has not slowed the rally much because the physical backdrop remains strained. Wilson’s view captures the tension: the market may be technically extended, yet that may not matter while prompt availability stays scarce and the delivery calendar is approaching. Price momentum and supply fear are feeding each other.
The next obvious catalyst is the third-Wednesday delivery date, which could force some positions to close or roll and test whether the squeeze has real staying power. After that comes the bigger policy variable: the US Commerce Department’s Section 232 refined-copper tariff decision, which StoneX’s Natalie Scott-Gray called the “biggest single catalyst.” That framing is telling. This is no longer just a copper rally. It is a market trying to price a potential policy shock before Washington actually moves.
Wilson also pointed to the logic behind the flow trade. “Normally you’d expect to get more Chinese deliveries into the LME… But the thing is, why would you deliver to the LME when you can still effectively ship metal into the US?” he said. That captures the core distortion: if metal can earn more elsewhere, the LME loses supply and the squeeze intensifies. Until the tariff picture clears, the London market may keep paying up for what little prompt copper it can get.
