I'm trying to use newer Anthropic models, including claude-opus-4-8, through the Bedrock Runtime and Bedrock Mantle APIs, but every request fails with an AccessDeniedException saying the model isn't available for my account. I'm seeing the same restriction with GPT 5.6 models. I've already granted the IAM user broad permissions, including the relevant Bedrock access policies, and opened a support case four days ago, but it still hasn't been assigned. Are these models controlled by an account-level availability flag, and is there a reliable way to request or escalate access?
3 Answers
If you need the models immediately, using Anthropic’s or OpenAI’s APIs directly may be the practical workaround. Another cloud provider could also have different approval requirements, though moving platforms may not be ideal if you specifically need Bedrock integration.
This sounds like an availability or approval restriction rather than a normal IAM problem. Some newer Anthropic and OpenAI models may require provider approval, account review, or a support-side enablement flag. A support case is probably necessary, although the initial response may simply reject access without explaining the escalation path.
IAM permissions alone may not be enough. Access to individual foundation models can be controlled separately at the account or provider level, so it’s worth checking whether an administrator has enabled the models in the Bedrock model-access settings for the target region. Also confirm that the model is actually offered in that region.
I’ve added the broad Bedrock and Mantle permissions to the IAM user, but the model is still denied. I’ll check the account-level model access and regional availability separately.
That’s what I’m running into—the request is rejected immediately, with no useful explanation of how to appeal or escalate it. I’ve sent the case information to support and am waiting.