Anthropic's growing pains mount ahead of OpenAI showdown

• Chief rival OpenAI senses opportunity in the Claude maker's recent stumbles, courting frustrated developers and pitching itself as the steadier alternative ahead of dueling IPOs.

Zoom in: Anthropic's problems over the past two months span nearly every part of its business — product quality, pricing, security and capacity — and are starting to compound.

1. Model backlash: Perceived declines in Opus 4.6 performance triggered an initial wave of suspicion, with some developers accusing Anthropic of quietly downgrading its flagship model.

• Its newest model, Opus 4.7, delivered major benchmark gains but drew a mixed public reception, as some users complained of higher token costs, bugs and uneven performance.

2. Capacity crunch: Surging demand is straining Anthropic's compute, with users running into tighter limits and periodic outages — a red flag for companies that have grown reliant on Claude.

3. Security scares: A software update accidentally exposed internal Claude Code files, handing outsiders a window into Anthropic's most valuable product and raising questions about its internal safeguards.

• Anthropic is now investigating reports that a small group of unauthorized users accessed Mythos — its most powerful model, withheld over safety concerns about its offensive cyber capabilities.

4. Product confusion: Some users discovered on Tuesday that Claude Code was no longer available on the $20/month Pro plan — a potentially major shift affecting Anthropic's most popular product and its most accessible tier.

• Facing massive backlash, the company said the move was part of a limited test affecting a small share of users, though that explanation did little to ease fears of broader pricing changes.

Reality check: Anthropic's business is still booming.

• Even as the company pushes enterprise clients toward usage-based pricing, demand hasn't slowed — nor has revenue.
• Anthropic's standoff with the Pentagon endeared it to AI safety advocates and Trump critics, helping drive a spike in usage that briefly sent Claude to the top of the U.S. App Store.
• "We've seen extraordinary demand for Claude over the past several months, and our team is doing everything we can to scale quickly and responsibly," an Anthropic spokesperson told Axios. "We know it hasn't always been smooth, and we're grateful to our community for the patience and feedback as we work through it."

The big picture: The stakes go far beyond a few product missteps. Anthropic and OpenAI are locked in a race to define the enterprise AI market and to convince investors they deserve massive IPO valuations.

• Anthropic's rapid rise has been fueled by cutting-edge products, developer trust and a reputation for discipline. Now, even small stumbles risk chipping away at that foundation.

What we're watching: OpenAI, no stranger to "code red" moments in the breakneck AI race, is seizing on its competitor's growing pains.

• A leaked memo from OpenAI chief revenue officer Denise Dresser blasted Anthropic as elitist and alleged that the company had overstated its revenue run rate by billions.
• CEO Sam Altman accused Anthropic of "fear-based marketing" in a podcast appearance this week, taking aim at its tightly controlled Mythos rollout.
• And as Anthropic grappled with user backlash from its Claude Code pricing confusion, OpenAI engineers — egged on by Altman — openly mocked their rival on social media.

The bottom line: Both Altman and Anthropic CEO Dario Amodei used to signal that the AI race should have multiple winners. Their tone and tactics now suggest otherwise.