BigBear.ai Holdings' stock plummeted 6.59% in post-market trading on Monday. The significant decline followed the release of the company's fourth-quarter 2025 financial results, which failed to meet investor expectations.

The AI solutions provider reported quarterly revenue of $27.3 million, missing the analyst consensus estimate of $33.31 million by approximately 18%. Revenue fell 38% compared to the same period last year, which the company attributed primarily to lower volume on Army programs. Furthermore, the quarterly gross margin contracted sharply to 20.3% from 37.4% in the prior-year period, due to the absence of significant one-time, high-margin contracts.

While the company reported a narrower-than-expected loss per share, the substantial revenue shortfall and declining profitability appear to have driven investor sentiment. The company's full-year 2026 revenue outlook of $135 million to $165 million also came in below the consensus estimate of $164.29 million, adding to concerns about near-term growth prospects.