European Patent Office upholds Solvay’s Soda Ash recycling patent

European Patent Office upholds Solvay’s Soda Ash recycling patent

Ruling secures critical milestone for Solvay in ongoing legal dispute with WE Soda

Brussels, June 16, 2026

Solvay announces that the European Patent Office (EPO) has upheld its European patent EP 3 971 138 B1 (“EP ’138”) following opposition proceedings initiated by WE Soda Ltd on February 13, 2025. The decision, issued after oral hearings on May 19, 2026, maintains the validity of the patent subject only to limited amendments. The decision may be subject to appeal.

Granted in May 2024, EP ’138 protects Solvay’s proprietary process for treating and recycling purge streams generated during sodium carbonate (soda ash) and sodium bicarbonate production. A process for manufacturing sodium carbonate (soda ash) and sodium bicarbonate comprising the patented recycling process is also protected by the patent, as are the products directly obtained thereof.

This outcome represents an important step in protecting Solvay’s innovation. EP ’138 is part of a patent family further including EP 2 878 579 B1 (“EP ’579”), which is currently the subject of separate litigation between Solvay and WE Soda.

In August 2021, Solvay initiated patent infringement proceedings before the Dutch courts against WE Soda and certain subsidiaries and affiliates, including two Turkish affiliates, based on the Dutch designation of EP ‘579. Solvay claimed that products derived from certain sodium carbonate treatment processes and methods at the Kazan Soda facility infringed its patent.

On December 3, 2025, the court ruled in favor of Solvay, upholding the EP’579 patent and granting, among other reliefs, an injunction in the Netherlands. The ruling comprises an order requiring the defendants, upon service of the judgment, to halt the import and supply of their products to the Netherlands. WE Soda Ltd and the relevant entities have appealed the Dutch decision. The appeal is pending.

The Solvay patent EP ‘138 now upheld by the European Patent Office is a unitary patent. Infringement actions brought before the Unitary Patent Court (UPC) based on unitary patents allow patent holders to act in one single, fast action covering at least 18 countries at once, with the opportunity to obtain an injunction to stop imports of infringing products.

Solvay believes that respecting patents and intellectual property is essential for fair competition. Solvay remains firmly committed to defending its innovations and will continue to take rigorous, decisive legal action to enforce its rights against infringers globally.

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About Solvay

Solvay, a pioneering chemical company with a legacy rooted in founder Ernest Solvay’s pivotal innovations in the soda ash process, is dedicated to delivering essential solutions globally through its workforce of over 8,400 employees. Since 1863, Solvay has harnessed the power of chemistry to create innovative, sustainable solutions that answer the world’s most essential needs such as purifying the air we breathe and the water we use, preserving our food supplies, protecting our health and well-being, creating eco-friendly clothing, making the tires of our cars more sustainable and cleaning and protecting our homes. Solvay’s unwavering commitment drives the transition to a carbon-neutral future by 2050, underscoring its dedication to sustainability and a fair and just transition. As a world-leading company with €4.3 billion in net sales in 2025, Solvay is listed on Euronext Brussels and Paris (SOLB). For more information about Solvay, please visit solvay.com or follow Solvay on Linkedin.