Apple CEO Tim Cook steps down after 15-year, $4.6 trillion tenure

Apple's market value grew from $347 billion to $4.6 trillion during Tim Cook's 15-year tenure as CEO, which ends Monday as hardware chief John Ternus takes the helm. Cook announced the succession in April, setting the transition for Sept. 1.

"I take enormous comfort in handing the helm to someone as brilliant and wonderful and capable as John," Cook wrote in a memo to employees obtained by 9to5Mac. "Few people understand what it takes to build products that change the world the way John does."

A $1,000 investment in Apple stock on the day Cook became CEO in August 2011 would be worth about $23,800 today, compared with about $6,550 for the same amount tracking the S&P 500. Revenue quadrupled from $108 billion in fiscal 2011 to $416 billion in fiscal 2025, while the services business — the App Store, iCloud, Apple Music, Apple TV+ and Apple Pay — grew to $109 billion in annual sales.

Cook, 65, becomes executive chairman and will continue managing Apple's relationships with President Donald Trump and the Chinese government. Ternus inherits a company trading near record highs, with shares up 15.3 percent in 2026, but faces questions about Apple's position in artificial intelligence relative to Big Tech peers.

Cook's Legacy: From Supply Chains to Services

When Steve Jobs named Cook as his successor in August 2011, investors were skeptical. The supply-chain executive was replacing a visionary, and Apple shares initially struggled. But Cook's operational expertise proved decisive, helping Apple navigate the pandemic, inflation and tariff pressures that disrupted global manufacturing.

The product portfolio expanded well beyond the iPhone. Cook added the Apple Watch, AirPods, Apple Pay, the Vision Pro and a services business generating more than $100 billion a year. iPhone sales alone jumped from $47 billion to $210 billion, though the device's share of total revenue shifted from 43 percent to just over half.

Berkshire Hathaway, which first acquired an Apple stake in 2016, built a position valued at more than $170 billion by 2023. Warren Buffett has repeatedly praised Cook's leadership, calling him one of the best CEOs in America. Though Berkshire has gradually trimmed its stake, Apple remains its largest single holding.

Ternus Inherits a Cash Machine With AI Questions

Ternus, who joined Apple in 2001 as a member of the product design team and was promoted to senior vice president of hardware engineering in January 2021, takes over at a moment of both strength and uncertainty. Apple's stock hit a record close of $339.79 on July 28, reclaiming the No. 2 spot by market value behind Nvidia.

But Apple has trailed Microsoft and Alphabet in the AI race, and the company recently raised prices on most hardware products and subscription services including Apple TV and Apple Music. The moves set the stage for what Apple has described as its most ambitious product cycle ever, with the foldable iPhone Ultra and iPhone 18 Pro expected at Wednesday's "Surprise and shine" event.

Cook's farewell dinner at Apple Park last week featured hours of tributes from Ternus, Laurene Powell Jobs and other current and former Apple executives, with OneRepublic performing. In his memo, Cook said he will miss the work "in ways I can only begin to imagine" even as he remains "completely at peace" with the decision.

"Together, we have created something far greater than any one of us could have imagined or accomplished alone," Cook wrote. "That's the secret to our success. We bring out the best in each other."

Apple shares closed Friday at $319.70, up about 11 percent in 2025 and 15.3 percent in 2026. The company's market cap of more than $4.6 trillion makes it the second-largest in the world, and Apple accounts for more than 6 percent of the S&P 500 index. Investors will watch Wednesday's product event for signs that Ternus can accelerate Apple's AI strategy, with the foldable iPhone Ultra expected to be the first major test of his product vision.

This article is for informational purposes only and does not constitute investment advice.