What the order says. DHS is publishing notice of an order under the Federal Acquisition Supply Chain Security Act of 2018 (FASCSA), issued after a Federal Acquisition Security Council review. It does two things. It excludes IT products and services developed by Hangzhou DeepSeek Artificial Intelligence Co., Ltd, affiliates included, from federal civilian agency procurements. And it orders removal of all DeepSeek and DeepSeek-affiliate products, plus third-party products and services developed using DeepSeek implementations, from civilian agency IT. The notice was filed for public inspection at 8:45 AM ET on Oct 19 (5:45 AM PT) and publishes Oct 20 as FR Doc. 2026-21447, docket DHS-2026-0628. CISA’s Cybersecurity Division runs implementation.
It’s been in force for months. Per CyberScoop, the notice carries a letter from Homeland Security Secretary Markwayne Mullin ordering the exclusion on June 26. Today is the public notice, not the start date. The letter cites DeepSeek storing data on servers in China, collection of user PII by DeepSeek-hosted models, and the risk that prompts and responses move sensitive data to the PRC. Agencies can ask for an exception, but they have to file 60 days ahead with a compelling justification such as a mission-critical function they can’t otherwise meet. Until removal is done, agencies are encouraged to watch traffic in and out, add logging and exfiltration controls on the affected systems, and flag anomalous activity.
Why vendors should care. The part that bites is the third-party clause. If you sell a SaaS product, an agent platform or a managed service to a civilian agency and any feature runs on DeepSeek weights, that feature is now something the customer has to remove. The order’s summary doesn’t carve out self-hosted open weights on US infrastructure, and DHS hasn’t said publicly how far “developed using DeepSeek implementations” reaches, for example whether fine-tunes or distilled models count. DeepSeek is the only model maker named. Moonshot (Kimi) and Alibaba (Qwen) are not in this order.
What we’d check. Build an AI bill of materials for anything you sell into government: which base models and fine-tunes each feature runs, who hosts them, and where the weights came from. Look for DeepSeek in model registries, inference endpoints and container images, along with the libraries that wrap it, and check any downstream supplier who might have quietly swapped in a cheaper model. On the buyer side, the interim steps in the letter are a solid baseline for any unsanctioned AI tool: egress monitoring to model API domains, logging on the systems that touched it, and DLP on prompts.