Antofagasta stock falls 1.39 percent as strike vote raises risk

Published on 09/28/2026 at 16:51 | Editorial responsibility: Rafael Müller, Editor-in-Chief AD HOC NEWS

Antofagasta stock was trading at GBp 3,678.00 on September 28, 2026, down 1.39 percent intraday. H1 revenue rose 18 percent to USD 4.5 billion, while copper output fell 9 percent.

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Antofagasta (ISIN GB0000456144) was trading at GBp 3,678.00 on the London Stock Exchange on September 28, 2026, down 1.39 percent from the previous close. The immediate risk is operational: unions at the Centinela copper operation scheduled a strike ballot for September 26 through September 28, 2026, according to TradingView.

Centinela risk meets growth spending

The ballot involves workers at a mine central to Antofagasta's expansion strategy. The Centinela second concentrator is intended to support higher copper volumes, so labor disruption would add execution risk while the project moves toward its 2027 commissioning target.

The market is also weighing a clear volume and price contrast. For the six months ended June 30, 2026, revenue rose 18 percent to USD 4.5 billion and EBITDA increased 27 percent to USD 2.84 billion, while copper production fell 9 percent to 285,000 tonnes, according to Openbook in its analysis of the August 13, 2026, half-year release.

Margins cushion lower copper output

That divergence shows why Antofagasta's earnings are currently more sensitive to realized prices and by-products than to tonnage alone. The first-half EBITDA margin reached 63.4 percent, five percentage points higher than a year earlier, while the realized copper price rose 36 percent to USD 6.19 per pound, according to Openbook.

Guidance remains the counterweight to that margin strength. Antofagasta reduced its 2026 copper production range to 625,000-655,000 tonnes from 650,000-700,000 tonnes, leaving the strike vote and the second-half production recovery as practical tests for the outlook.

Analyst target stays above the market

Sharecast reported on September 14, 2026, that Berenberg upgraded Antofagasta from Hold to Buy while keeping its price target at GBp 4,400.00. That target stands 19.66 percent above the GBp 3,678.00 intraday price, but the strike ballot adds a company-specific risk to the volume growth case.

Antofagasta stock trades below its yearly high

Antofagasta stock was trading at GBp 3,678.00 on the London Stock Exchange at 3:49 p.m. BST on September 28, 2026. The session volume was 297,484 shares, and the 52-week range was GBp 2,496.00 to GBp 4,475.00.