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.