The Department of War’s M&A Review Guidance: What Companies in the Defense Industry Need to Know

In February 2026, the Department of War (“DoW”) issued guidance implementing Section 857 of the FY2024 NDAA and elevating the DoW’s historically ad hoc role in defense-related M&A review to a mandatory, though nebulous, notification requirement on the transaction parties. Section 857 addressed the perceived inadequate participation of DoW in the review of defense-related M&A transactions, which amounted to only about 10% of those transactions annually. A 2023 GAO report noted t