U.S. Government Contract Stocks Plunge 12% Post-Earnings, Losing 560 Billion Won in a Day

Amentum Holdings Inc. (NYSE: AMTM), a U.S. government and defense engineering firm, closed at $32.06 per share on the New York Stock Exchange on the 10th, down 12.33% from the previous trading day. Its market capitalization fell to about $3.77 billion, wiping out roughly $410 million in value in a single session.

The steep drop came after the company’s fiscal 2026 first-quarter results showed revenue of approximately $3.2 billion—a 5% year-over-year decline that missed Wall Street forecasts—while adjusted earnings per share slightly beat consensus. Added to this mixed performance was a conservative outlook for the rest of the year, which U.S. media cited as the main trigger for the sell-off. Nevertheless, analysts have maintained a “moderate buy” consensus rating on Amentum, with a 12-month price target in the mid-$30 range. At its early-February annual meeting, shareholders also reapproved the existing board and executive compensation, signaling confidence in the company’s governance.

Headquartered in Chantilly, Virginia, Amentum provides engineering and technical services to the U.S. federal government and allied nations, covering intelligence analysis, cyber-security, and space and digital solutions, as well as nuclear-power support, environmental remediation, and defense logistics and maintenance. Launched in 2020 following the spin-off of AECOM’s federal-services division, the company has grown through integrations with DynCorp, PAE and others into a major defense contractor with over 50,000 employees, and is included in several small-cap indices.