The Big Four consulting firms are embedded in Big Tech. Here's who audits each of the Magnificent 7 companies.

"Apple, Microsoft, Alphabet, Amazon, Nvidia, Meta, and Tesla, known as the Magnificent Seven, now have a combined market value of over $20 trillion, making them among the most powerful companies in history. Who is handling their financial records? Another numerically-termed group of powerhouses. The Big Four professional services firms - PwC, Deloitte, EY, and KPMG - are the industry-leading consulting and accounting firms that audit the Magnificent Seven."

"The Big Four are also becoming increasingly embedded in the tech sector itself as they work to provide clients with AI. Deloitte has partnerships with Apple, Alphabet, Microsoft, and Nvidia. While EY has key relationships with Microsoft and Nvidia. Behind the sky-high valuations and global dominance, the Big Four firms independently assess how these companies report their finances, run internal controls, and follow the rules. Audits are a crucial mechanism for ensuring accountability to shareholders, regulators like the SEC, and other stakeholders."

"Shareholders ratify the appointment of Microsoft's auditor annually at the annual shareholder meeting. Under SEC rules, Microsoft's outside auditor is required to regularly rotate the key audit partner, at least every five years. Deloitte, the largest of the Big Four by revenue and employee numbers, has been Microsoft's public auditor since its IPO in 1986, according to a statement from its annual shareholder meeting."

The Magnificent Seven of tech now exceed a combined market value of more than $20 trillion. The Big Four professional services firms—PwC, Deloitte, EY, and KPMG—audit those largest tech companies and evaluate their financial reporting, internal controls, and regulatory compliance. Audits provide accountability to shareholders, regulators such as the SEC, and other stakeholders. The Big Four are increasingly embedded in technology through AI partnerships: Deloitte partners with Apple, Alphabet, Microsoft, and Nvidia, while EY has relationships with Microsoft and Nvidia. Deloitte has audited Microsoft since its 1986 IPO; Microsoft paid Deloitte $78.4 million in fiscal 2025.

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