BESI shares tumbled 13% Thursday after a South Korean report suggested major chipmakers might relax next-gen high bandwidth memory (HBM) thickness standards, potentially undermining demand for the Dutch firm’s hybrid bonding technology. The stock fell to €163.90 from €188.65, a drop extending its decline below the €197.60 52-week high. The catalyst: a ZDNet Korea article cited industry sources claiming JEDEC members—including Samsung, TSMC, and Nvidia—are discussing raising HBM thickness standards from 775 to 825-900 micrometers for HBM4E and HBM5, requiring 20-layer DRAM stacking. Hybrid bonding, a precision process central to BESI’s growth strategy, faces reduced urgency if standards ease, as thermocompression bonding (cheaper but less advanced) could remain viable.

ZDNet Korea noted sources mentioned 900+ micrometer thresholds, with JEDEC typically finalizing standards 1-1.5 years pre-commercialization.