Materion is trading at $135.99, down 46%, with no credible September 22 company-specific catalyst identified. - Regular-session trading closed at $253.44 on September 22, 2026; no announcement, earnings release, guidance change, acquisition, or regulatory event was identified. - Materion’s latest clearly documented results were released August 5; its investor-relations filing page shows no newer major filing through September 18. The broader market was mixed; recheck for a delayed disclosure or pricing anomaly.