Space Defense Stocks: $500 Million Market Cap Vanishes in a Day After Performance Rally Ends

York Space Systems Inc. (NYSE: YSS) closed at $32.39 on the New York Stock Exchange on the 11th (local time), plunging 9.73% from the previous day. Trading volume rose to about 1.47 million shares, and its market capitalization fell to roughly $4.1 billion (≈5.6 trillion KRW), erasing approximately $370 million (≈500 billion KRW) in value in a single session.

On March 19, the company released its full-year 2025 results, reporting a 52% increase in revenue and a reduced net loss, and projected a return to adjusted EBITDA profitability in 2026. In February, it won a $187 million contract to build a constellation of more than 20 commercial satellites based on its M-Class platform. In March, it acquired electric-propulsion provider Obion Space Technologies, bringing a critical supply-chain component in-house.

Headquartered in Denver, York Space Systems is a prime contractor in the space and defense sector, supplying small-satellite platforms—including S-Class, LX-Class and M-Class—for customers such as the U.S. Department of Defense’s Proliferated Warfighter Space Architecture. The company went public on the NYSE on January 30, pricing its IPO at $34 per share and raising about $582.6 million (≈780 billion KRW), underscoring an aggressive growth strategy.