The semiconductor sector is experiencing a significant pre-market decline, continuing a sharp sell-off from the previous session. The downturn is primarily fueled by investor anxiety regarding the sustainability of the AI-driven rally and lofty valuations. Taiwan Semiconductor Manufacturing Co. (TSMC) raising its capital expenditure forecast, despite strong earnings, has intensified concerns about rising costs and pressure on margins. The Philadelphia Semiconductor Index has entered a technical bear market, signaling a broad-based reassessment of the industry's near-term growth prospects.