Solvay: European Patent Office Upholds Patent Against We Soda
The European Patent Office confirmed on Tuesday the validity of Solvay's European patent EP 3 971 138 B1, which pertains to its proprietary process for treating and recycling streams generated during the production of sodium carbonate (soda ash). This decision comes after opposition proceedings initiated by competitor WE Soda and strengthens the Belgian chemist's position in its legal disputes.
A Key Patent for the Soda Recycling Process
The patent upheld by the European Patent Office protects Solvay's proprietary process for treating and recycling purge streams generated during the production of sodium carbonate and sodium bicarbonate. The same patent also covers the manufacturing processes of sodium carbonate that incorporate this recycling, as well as the products directly derived from these processes. The decision was made after oral hearings held on May 19, 2026, following the initial opposition filed by WE Soda on February 13, 2025. The patent was maintained subject to limited amendments and remains subject to appeal.
A Component in a Comprehensive Strategy to Defend Innovations
This patent is part of a broader family of patents including European patent EP 2 878 579 B1, which is currently at the center of a separate litigation between Solvay and WE Soda in the courts. On December 3, 2025, a Dutch court ruled in favor of Solvay on this second patent, confirming its validity and notably granting an injunction that ordered the cessation of imports and supply of products to the Netherlands. WE Soda has appealed this decision, with the case still ongoing. Solvay emphasizes that the now-confirmed patent is a unitary patent, allowing the group to defend its rights in front of the Unified Patent Court and covering at least 18 countries in a single action.
