Copper Hits a Wall: What Shanghai's Inventory Surge Really Means

By Siam Sukkhee Trading Co., Ltd — 2026-10-25 — Bing News — zinc price LME

Copper had a rough week. The metal dipped 1.31% to 110,565 RMB/ton by October 16, though it's still up nearly 30% year-on-year. Nothing earth-shattering on the surface. But the mechanics under the hood matter more than the headline move.

The Shanghai Futures Exchange reported a 20,000-tonne jump in copper inventory last week. That's not trivial. It broke a four-week run of falling stocks and immediately spooked the market—the spot premium over front-month contracts narrowed sharply, from 1,080 RMB/ton to 420 RMB/ton. The "short squeeze" that had been supporting nearby prices loosened its grip.

On first read, it looks bearish. Inventories rising, prices falling. Trade press would call it correlation. But here's where it gets interesting.

The real story sits on the supply side. Treatment charges for copper concentrate have plummeted to minus $238 per tonne—the lowest since September 2007. That's not a figure you see often. Smelters pay this, which means they're losing money on every tonne they process. The rational response? Cut production. So they did. October output is tracking to 1.0847 million tonnes, marking the year's low. This time the cuts aren't routine maintenance. They're deliberate.

Meanwhile, spot treatment charges don't lie. When negative, miners have to pay smelters to take concentrate. That's scarcity in its purest form.

Demand, by contrast, is doing what high prices usually force it to do: backing away. When spot copper spiked to 112,160 RMB/ton early last week, downstream cable manufacturers and rod-makers shifted to a wait-and-see posture. Trading only picked up after prices retreated. The operating rate for cable makers slid to 60.19%, down nearly 2 percentage points month-on-month. September saw refined copper consumption fall to 1.39 million tonnes—roughly 60,000 tonnes below last year's level during what should be peak season.

Not much to celebrate there.

But—and this matters—structural demand hasn't evaporated. Power grid investment is supposed to accelerate in Q4. New energy vehicle sales are tracking toward 19 million units for the year. Energy storage keeps humming. These aren't trivial buckets.

Macro conditions have turned ugly. The Federal Reserve's September minutes suggested officials might still hike rates before year-end. September's CPI came in hotter than expected, which reignited rate-hike chatter. The US dollar has stayed elevated, which crushes demand for priced-in-dollars commodities. All of that pushed down copper valuations last week without any fundamental shortage materializing. Actually, that's not quite right. The shortage existed—it just shifted from the headlines into the weeds.

The LME side tells part of the same story. London copper inventories fell by 6,425 tonnes to 226,600 tonnes. Cash-over-three-month spreads remain in backwardation, meaning spot copper trades at a premium to forward positions. That's the textbook signal for physical tightness. Overseas buyers still can't find copper easily. The London data and the Shanghai inventory build are less contradictory than they seem. Shanghai got a shipment; that explains the rise. London remains squeezed; that explains the backwardation.

The market narrative flipped last week from production anxiety to inventory levels and basis spreads. It's a healthy conversation. But medium-term the arithmetic hasn't shifted. Concentrate supply is clamped. Smelters are shrinking runs because the economics don't work. You can't expand smelting output by wishing. It takes years to build capacity. That floor—smelter losses pushing toward 5,000 RMB/ton—will eventually matter more than weekly warehouse moves.

Copper prices are likely to stay choppy, biased lower, until something breaks the current stalemate. High prices kill demand. That demand loss then eases the supply pressure, which gives prices room to breathe lower. Somewhere in that cycle sits an equilibrium. Finding it is the game.

Source: Investing News Network

Tags: zinc smelting industry news