TechFlow reported that on June 13, Claude issued an announcement saying it will suspend access to the Fable 5 model for all users because of a related U.S. government ban. The change covers both regular Claude conversations and usage through Claude Platform, meaning users and developers who have been using Fable 5 need to move to other Claude models.
According to the announcement, newly created sessions will no longer continue with Fable 5. Instead, they will switch to the default model previously set by the user, or to Opus 4.8 if that default path applies. Claude also stated that Fable 5 sessions that are already open will return an error and be terminated, so users will not be able to continue interacting with the model inside those existing sessions.
The developer-side impact is also direct. API requests to Fable 5 made through Claude Platform will return errors. Claude is asking developers to migrate affected applications and integrations to other Claude models as soon as possible, in order to avoid failures in services that depend on Fable 5 after access is paused.