GRAM augments the standard Transformer architecture by adding small auxiliary modules—essentially dedicated neurons at every layer—that are intended to capture specific dual-use capabilities during training . The key mechanism is gradient routing: during backpropagation, weighted masks control which parameters update for which data
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Once training is complete, individual modules can be removed or disabled to reduce access to a particular capability, or left in place for deployments that are permitted to use that knowledge . Because each dual-use category maps to its own module, a single GRAM-trained model with four categories can theoretically be configured into 2⁴ = 16 distinct capability profiles by toggling each module on or off independently
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The GRAM research arrives alongside a high-stakes real-world example of the problem it aims to solve. In June 2025, the Trump administration imposed export controls on Anthropic's Claude Fable 5 and Mythos 5 models after cybersecurity concerns, blocking access for any foreign national—inside or outside the U.S., including foreign-national Anthropic employees . The ban lasted 18 days before the Commerce Department lifted it after a national security review
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This episode illustrates the current state of AI access control: an entire model—with all its capabilities—gets treated as a single indivisible unit. If a model has a dangerous capability, the only option today is to withhold the entire system. GRAM proposes a finer-grained alternative: instead of locking down an entire model, a system could allow or disable specific categories of knowledge depending on the deployment context .
Anthropic's researchers explicitly identify GRAM as preliminary work and highlight several limitations :