EY Emerges as Likely Anthropic Auditor as Rival Big Four Firms Deepen AI Ties
The Financial Times says the evidence points towards EY as Anthropic’s auditor, as commercial relationships between the AI company and Deloitte, PwC and KPMG highlight an emerging independence problem
Anthropic, the company behind Claude, has not publicly identified its auditor. But three of the four largest global accounting firms now have significant commercial relationships with the company, creating independence issues that exclude them from auditing the company - and the last one standing is EY.
PwC announced in May that it was expanding its strategic alliance with Anthropic, rolling out Claude products across its own workforce, establishing a joint centre of excellence and training and certifying 30,000 PwC professionals.
Days later, KPMG announced a global alliance under which Claude would be embedded in its Digital Gateway platform, with Anthropic naming KPMG a preferred partner for private equity and the companies agreeing to develop new Claude-powered products together.
Deloitte’s relationship with Anthropic goes back further. The firms first announced an alliance in July 2024, and by April 2025 Deloitte had launched a Claude-focused training and certification programme targeting 15,000 professionals globally. In October, the alliance expanded again, with Deloitte making Claude available to more than 470,000 people across its global network and establishing a Claude Center of Excellence.
US auditor-independence rules require auditors to be independent of their audit clients both in fact and appearance and place restrictions on business relationships between an accounting firm and an audit client. The SEC’s broader test asks whether a reasonable investor, knowing all the relevant circumstances, would regard the auditor as capable of exercising objective and impartial judgment.
The Financial Times concludes that the available evidence points towards EY, which does not appear to have an equivalent commercial alliance with Anthropic, as the most plausible candidate. It stresses, however, that Anthropic’s auditor has not been officially confirmed.
The independence issue may become increasingly significant as the Big Four race simultaneously to sell AI-related consulting services, embed third-party AI models into their own products and maintain their traditional role as independent auditors of the world’s largest companies.
The question is no longer simply which accounting firm has the technical capability to audit an AI company. It is also which firms remain sufficiently independent to do so.
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