ASE Technology's stock experienced a significant decline of 5.18% during the overnight session, as the semiconductor company was caught in a broader sector sell-off.

The drop was attributed to sustained selling pressure across the semiconductor industry, with major peers including Intel, Micron Technology, Advanced Micro Devices, NVIDIA, and Broadcom all posting declines in recent sessions. This systemic weakness in the sector continued to weigh on individual stocks like ASE Technology.

Despite ASE Technology's reported strong fundamentals, including robust first-quarter earnings and strategic expansions in high-end testing capacity for AI and automotive electronics, the short-term, sector-wide negative sentiment overshadowed these positive developments, leading to the stock's decline.