Humana (HUM) shares plummeted 5.03% in intraday trading on Monday, as the health insurance sector faced multiple headwinds. The stock's decline comes amidst growing uncertainty surrounding the Affordable Care Act (ACA) subsidies and a reduced price target from analysts.

The primary driver of the sell-off appears to be the recent U.S. government shutdown deal, which notably excluded an extension of ACA subsidies. These subsidies, introduced during the COVID-19 pandemic, are set to expire at the end of 2025. The Senate's agreement to postpone the vote on extending these subsidies until December has created significant uncertainty in the health insurance market. Without congressional action, an estimated 24 million enrollees could face sharp premium increases for their 2026 plans, potentially more than doubling their monthly costs.

Adding to the pressure, former President Trump urged Republican senators to redirect federal money used for ACA marketplace subsidies directly to individuals for buying coverage. This proposal has further unsettled investors, as it could significantly impact the business model of health insurers like Humana. Moreover, Truist Securities adjusted its price target for Humana to $285 from $300, while maintaining a Hold rating, reflecting growing caution among analysts about the company's near-term prospects. The combination of these factors has led to a broad decline in health insurance stocks, with Humana being particularly hard hit in today's trading session.