Claude Fable 5.1 in Copilot won't run without retention

Four of the five Claude model-and-tier cells that the first release of a new AI data retention tracker could verify keep prompts by default, reports Provenbrief. All five are Anthropic commercial surfaces, and each retention state is tied to a dated policy document from the provider itself.

At a glance

• Retention in Copilot is a condition of use rather than a setting: Fable 5.1 and Fable 5 will not run unless Anthropic keeps prompts and outputs to operate its safety classifiers.
• Every other Claude model in Copilot runs at zero retention, Claude Enterprise keeps conversations indefinitely by default with a 30-day floor on custom periods, and Covered Models under a BAA sit at 30 days.
• An unapproved Copilot Business organization has no zero-retention option for either model across the 121 days from September 1 to December 31, 2026, and the replacement safeguard carries no date.

Retention has generally been treated in enterprise procurement as a switch that can be thrown, and this mapping suggests that framing no longer holds across Anthropic's own commercial surfaces, where it appears as a default, as a condition of use and as a floor, depending on the cell. For buyers with HIPAA obligations the grid has no fully covered corner, which likely shifts the purchasing question from how long data is kept to whether zero retention can be bought for a given model at all.

Two Claude models in Copilot cannot run without retention

Claude Fable 5.1 reached general availability in GitHub Copilot on September 1, 2026 on the Pro+, Max, Business and Enterprise plans, and GitHub's changelog states that retention of prompts and outputs is required to operate Anthropic's safety classifiers. Fable 5 in Copilot carries the same requirement.

Copilot Business and Enterprise administrators have to switch the model on themselves, and enabling it acknowledges the retention requirement. Retained data is not used to train Anthropic's models, according to the changelog, and the tracker scores training as an axis separate from retention. Every other Claude model in the product operates under zero data retention, while no retention duration is stated for either Fable model on the cited page.

The ZDR exemption runs 121 days, to December 31, 2026

The tracker's second metric, ZDR Lag, counts days from a model's launch to the date a typical paying customer can run it with zero retention. Eligible enterprises get that on day zero: approved requests route to ZDR endpoints under the exemption, eligibility runs through the GitHub account team rather than a published setting, and GitHub Support cannot determine eligibility or enable access.

The exemption covers Fable 5.1 and Fable 5 with zero data retention "through the end of the calendar year", in the changelog's wording, on a post dated September 1, 2026. After that point, continued use of either model in Copilot requires Enterprise Frontier Safeguards, whose phase-in is dated only as "later this fall".

Covered Models under a BAA are held at 30 days with no ZDR

Anthropic's privacy documentation states that Covered Models require 30-day data retention and are not available with zero data retention enabled. The same document covers Claude Code under a Business Associate Agreement only when ZDR is switched on, and draws the consequence itself: those services cannot use Covered Models under the agreement.

Several Claude Code surfaces, including desktop remote mode, the web beta and Computer Use, are listed as incompatible with ZDR altogether. Outside Copilot, Claude Enterprise conversations and projects are retained indefinitely by default, following the custom retention controls Anthropic shipped on March 16, 2026, where an owner-set period is floored at 30 days counted from last activity.

When the exemption lapses

The end date is fixed at December 31, 2026, but the condition that replaces it is not. The Enterprise Frontier Safeguards phase-in carries no date beyond "later this fall", and the programme is described as "complete privacy (the same as a zero data retention policy)", with data stored in cloud infrastructure controlled entirely by the customer while automated safety monitoring continues. No retention window has been published for either Fable model in Copilot.