Anthropic Leaks Claude Fable 5.5 and Next-Gen Opus Ahead of IPO

Two new Claude models have surfaced ahead of Anthropic's public listing: Fable 5.5, and a next-generation Opus. Both are said to be in early testing, with screenshots already circulating on X and Discord. If the timeline holds, the first of them could arrive as soon as next week.

How Fable 5.5 Leaked

The first clue came from Azure. Observers spotted a listing for claude-fable-5-5 in the Azure model catalog; it was removed shortly afterward, but screenshots had already spread. That was followed by a wave of early test images posted by users.

The most-discussed demo is the familiar "pelican on a bicycle" prompt, a long-running visual benchmark for image-generation quality. Observers noted that Fable 5.5's output looked closer to a top-tier image model than a text-and-vision assistant: the pelican appears to be holding a fish in its beak, bicycle-wheel tracks are visible on the sand, and the lighting on the wheels itself reads as physically consistent. A separate game-controller demo showed more incremental gains, but Fable 5.5 still produced visibly more detail than the recently released Opus 5.5.

More test images are expected as the model moves through early access. The pelican prompt itself is becoming over-trained, and the community is already asking for fresh visual tests.

Next-Gen Opus Spotted as "Obsidian 3"

Before the Fable 5.5 discussion settled, a second signal appeared. Developers tracking benchmark platforms found a model listed under the codename Obsidian 3, with scores sitting slightly above the current Opus 5.5. The implication is that the Opus line itself is about to move again, only weeks after Opus 5.5 shipped.

The cadence is striking. Google has been shipping new models roughly every two weeks, and Anthropic is now showing that it can respond on a similar schedule rather than letting a single release carry the narrative for months.

Why the Rush Before an IPO

The timing is not accidental. Anthropic recently filed its S-1 prospectus with the U.S. Securities and Exchange Commission, formally starting its IPO process. Market discussion of the valuation has reached the $1.5 trillion to $2 trillion range, which would put the listing among the largest in history and potentially ahead of SpaceX's private round.

For a company about to go public, the most direct way to show strength is product velocity. Filing logs, benchmark gains, and a visibly crowded roadmap do more marketing at this stage than safety-themed essays. The expectation is that both Fable 5.5 and the next Opus will land around the IPO window, and people familiar with the matter say the wait may be shorter than the event itself — on the order of one to two weeks rather than months.

The broader read is that Anthropic is no longer treating model releases as occasional, carefully staged events. In the run-up to one of the most anticipated listings in tech, the roadmap is the pitch deck.