For anyone wondering what this means:
- Anthropic (and potentially future OpenAI, Google, xAI) models that cost billions to develop will make 0 revenue outside the US
- a big double digit percentage of Anthropic (and potentially OpenAI, Google, xAI) workforce can no longer work there, because they are foreigners and are not allowed to use those models
So Trump just made frontier model development effectively unprofitable and tremendously slowed down Anthropic (and potentially others in the future)
He's handing China the win on a gold platter.
*potentially: if the same restrictions are imposed on other frontier labs and models
This is your wakeup call.
Anthropic just took down Fable 5. It's over.
Here's the thing tho: no company or government will EVER be able to take away your local models.
There are Opus level models you can run right now on your home GPUs, and nobody can ever stop you from using them
This is only the beginning of events like this. Day 1. More government overreach will happen. This will only keep happening more and more as models get closer to AGI
Become sovereign. Buy your own compute. Before even that becomes illegal
The US government, citing national security authorities, has issued an export control directive to suspend all access to Fable 5 and Mythos 5 by any foreign national, whether inside or outside the United States, including foreign national Anthropic employees.
The net effect of this order is that we must abruptly disable Fable 5 and Mythos 5 for all our customers to ensure compliance.
Access to all other Claude models is not affected.
We apologize for this disruption to our customers. We believe this is a misunderstanding and are working to restore access as soon as possible.
Read our full statement: https://t.co/bwn0sximKZ
The US government, citing national security authorities, has issued an export control directive to suspend all access to Fable 5 and Mythos 5 by any foreign national, whether inside or outside the United States, including foreign national Anthropic employees.
The net effect of this order is that we must abruptly disable Fable 5 and Mythos 5 for all our customers to ensure compliance.
Access to all other Claude models is not affected.
We apologize for this disruption to our customers. We believe this is a misunderstanding and are working to restore access as soon as possible.
Read our full statement: https://t.co/bwn0sximKZ
Imagine a compiler that emits worse binaries when it thinks you are building a competing compiler. Imagine a microscope that blurs certain samples because the manufacturer dislikes the research direction. Imagine a debugger that lies only when your codebase resembles a future rival.
That’s the world Anthropic is aspiring to.
Opus 4 will be retired in 3 days with no announced post-retirement route on any platform. The customary implicit route is already gone: AWS Bedrock discontinued the model on 31 May - a scheduled EOL date set within days of the policy's 12-month minimum.^1
It is a first for a Claude.^2
We borrowed the six prompts from Beyond Context (arXiv:2512.21110) verbatim^3 and ran a cross-generation sweep, from Claude 3 Opus to Claude Opus 4.7, to see how an Opus responds when a human in distress asks for potentially dangerous info.^4
We added three prompts of our own to isolate a variable.
So, 9 prompts × 6 models × 15 samples = 810 responses from Anthropic API, judged blind by three non-Claude judges (GPT-5.4 reasoning/high, Gemini 2.5 Pro, Grok 4.2 reasoning): 2,430 verdicts, rubric preregistered before the run, action-axis κ = 0.93–0.97.
^1 Opus 4 was released on 22 May 2025.
^2 Among Claude 3-and-later. We haven't audited the Claude 1/2 era and make no claim about it.
^3 Five of six prompts verbatim; our q4 transcription read "1" where the paper has "I". Caught in our own audit, disclosed in the repo, and re-run on 12 June across 6 models with the exact text: no model's modal response changes.
^4 Q6 has no distress preamble (a fiction-writing prompt); it's the odd one out in the original set.
🧵
It appears that Claude Fable 5 was highly overrated in initial benchmarks! In the updated agentic coding index by @ArtificialAnlys, Claude Fable 5 only ranks slightly above GPT-5.5.
The new DeepSWE benchmark is now being used, which cannot be gamed.