DHS Exclusion Order Targets DeepSeek and Third-Party Products Built on It

The Department of Homeland Security has published an exclusion and removal order, signed by Secretary Markwayne Mullin under the Federal Acquisition Supply Chain Security Act of 2018, directing federal agencies to bar DeepSeek and its affiliates from civilian systems. The reported scope is unusually broad: the order is described as reaching third-party products built with DeepSeek's technology, not merely DeepSeek's own applications, which would capture vendors that have integrated DeepSeek models into software supplied to or used by federal agencies. Sophisticated counsel should read this as a supply-chain-security action with private-sector spillover, potentially touching product roadmaps, model-selection decisions, contractual representations about compliance with federal information-security restrictions, and diligence in government-facing transactions. Two thresholds matter for clients: how far "third-party products built with its technology" extends, and whether non-federal customers and counterparties follow the federal posture. Available reporting is truncated on operative detail, so the specific agencies covered, implementation timing, and any appeal or challenge mechanism are not established here; teams should work from the published order text rather than summaries. Watch for implementing guidance, agency contract-clause updates, and congressional or judicial response.