Tim Cook is stepping down as Apple’s chief executive after more than a decade at the helm, handing the company’s top job to John Ternus in a succession that places product development and hardware expertise at the center of Apple’s next phase.

Cook, who became CEO in 2011 after succeeding co-founder Steve Jobs, will remain with Apple as executive chairman. In that role, he is expected to continue overseeing key political and government relationships, including those involving U.S. President Donald Trump and the Chinese government.

In a farewell memo to employees on his final day as CEO, Cook sought to reassure staff that his departure from the top executive role does not mark an exit from the company. He described Ternus, Apple’s senior vice president of hardware engineering, as exceptionally suited to lead the company.

“As you know, I am not leaving Apple. But I am stepping away from a role that I have loved deeply,” Cook wrote. “Few people understand what it takes to build products that change the world the way John does and I could not be more excited for his leadership.”

The appointment gives Ternus responsibility for Apple at a consequential moment. The company is facing pressure to translate artificial intelligence advances into products, defend its position in China, sustain growth in its services business, and navigate an increasingly complex regulatory environment.

Ternus brings a product-focused background to the role. As head of hardware engineering, he has been closely involved in Apple’s device portfolio, including recent product launches such as the ultra-thin iPhone Air, lower-cost MacBook Neo and AirPods with hearing-health capabilities.

His promotion is believed to signal a stronger emphasis on Apple’s traditional strength: integrating hardware, software and silicon into tightly controlled consumer products. That strategy could become even more important as AI shifts competition from standalone software and cloud services toward devices capable of running sophisticated models.

Apple has already been adjusting its hardware strategy around AI demand. The company brought forward the release of new Mac models, including the Mac mini and Mac Studio, as demand for AI-capable computing increased.

The leadership change also comes as Apple confronts a more difficult competitive environment. Rivals are investing heavily in generative AI and AI agents, while Apple has faced scrutiny over the pace of its AI development. The company’s ability to integrate AI into the iPhone and other devices without compromising privacy, performance, or its tightly controlled ecosystem will be a major test for Ternus.

Cook’s continued presence could provide some continuity on issues that extend beyond product development. His relationships with policymakers are of the essence as Apple navigates U.S. technology regulation and its extensive manufacturing and supply-chain exposure to China.

Cook has also developed a close working relationship with Trump, who has repeatedly focused on Apple’s manufacturing footprint and investment in the United States. Remaining as executive chairman allows Cook to retain an active role in those relationships while leaving day-to-day operational leadership to Ternus.

In his memo, however, Cook largely avoided discussing Apple’s strategic challenges. Instead, he focused on the company’s culture and the people who built it.

“There is something truly special about Apple,” Cook wrote, saying he was most proud of achievements that could not be captured in an annual report. He noted that Apple’s culture had been central to its success and invoked Jobs’ famous description of making a “dent in the universe.”

Cook also used his final day as CEO to publicly endorse Ternus, an important signal to employees, investors and Apple’s broader ecosystem that the succession has his full support.

“I take enormous comfort in handing the helm to someone as brilliant and wonderful and capable as John,” Cook wrote.

On X, Cook said the change in title would not alter his connection with Apple.

“My title changes tomorrow, but the love I have for the Apple community never will,” he wrote.

For Apple, the significance of the transition goes beyond a change in title. Ternus inherits a company with enormous financial resources and one of the world’s most valuable consumer brands, but also one confronting a technology shift that could reshape the economics of smartphones, personal computers and digital services.

His first major challenge will be demonstrating that Apple can turn its hardware advantage into a durable AI advantage, while maintaining the product discipline that defined his rise through the company.

Full memo below:

Team,

Today is my last day as CEO of Apple. This is a moment I always knew would come one day, and yet it is still hard to believe it has arrived and I am writing these words. I love this company and the team behind it, and I couldn’t let this day pass without sending a note to you to tell you how grateful I am for the outpouring of affection you’ve sent my way, for the way you’ve shown up each and every day, and most of all, for the privilege of a lifetime serving as your leader.

The truth is, whatever there is to say about my success, I know it is all because of you. You have brought out the best in me. In all my life, I have never seen or been with such an extraordinary team of people before, and every day I get to see more examples of that.

There is something truly special about Apple. I am most proud of what an annual report could never capture. This place is proof that culture triumphs over everything. We share a belief that what we build matters and that we have both the opportunity and the responsibility to leave the world better than we found it. That purpose is part of what makes this place extraordinary. Apple helps nurture it, but I believe it lived within each of you long before you arrived here. It is what brought you to this company and what continues to drive the work you do every day.

Together, we have created something far greater than any one of us could have imagined or accomplished alone. And that’s the secret to our success. We bring out the best in each other. We lift each other up. We have made it possible to leave our “dent in the universe,” as Steve once described it, because of who we are and what we believe, because of what we value and how we see the world. How fortunate we are. How fortunate I am.

As you know, I am not leaving Apple. But I am stepping away from a role that I have loved deeply. I will miss this work in ways I can only begin to imagine, even as I remain completely at peace with my decision. I will miss leading you and being with you for every step, even as I take enormous comfort in handing the helm to someone as brilliant and wonderful and capable as John. Few people understand what it takes to build products that change the world the way John does and I could not be more excited for his leadership.

I hope you know how much I appreciate you and what an honor it has been to be your CEO. Most of all, I hope you will continue to be proud to be part of this remarkable place we call Apple and always give it your very best. When we bring our whole selves to this work, with care for one another and for the people we serve, there is no limit to the profound difference we can make.

French chip materials maker Soitec is using a surge in demand for wafers used in AI data-center optics to secure multi-year customer commitments, with deposits and fixed pricing designed to give the company greater visibility over future demand and protect its margins.

The strategy comes as hyperscalers race to expand AI computing infrastructure and increasingly turn to optical connections to move data between processors. Copper connections are becoming less attractive for some high-speed applications because of their power consumption and performance limitations, increasing demand for silicon photonics.

“We are using the current situation to find the right balance between the value we bring and the price we can ask,” Soitec CEO Laurent Remont told Reuters.

Soitec told investors last month that revenue from photonics-SOI, the silicon substrate used to manufacture silicon photonics chips, would more than double in the current financial year from slightly above $100 million. Remont said that forecast now represents “absolutely a floor,” implying revenue of more than $200 million.

The acceleration is of the essence to Soitec because silicon photonics is becoming an increasingly important component of AI infrastructure. As AI systems require ever greater volumes of data to move between computing and networking components, optical technology offers advantages in speed, distance and energy efficiency.

Soitec supplies the substrate used by almost all silicon photonics chips, according to UBS, which estimates the French company controls about 95% of the market. Its shares have almost quadrupled this year as investors have bet on the company benefiting from the expansion of AI-related optical networking.

Rather than simply expanding capacity immediately, Soitec is seeking to make customers commit capital alongside their orders.

About 80% of the company’s capacity reservation agreements with more than 10 photonics customers are expected to be signed within the next one to two weeks, with the remainder expected within a month, Remont said.

The agreements will lock in prices and require customers to put down deposits against committed volumes. Customers that take the agreed quantities will have their deposits returned, while those that fall short will forfeit them. Orders above contracted volumes will be subject to fresh pricing negotiations.

“That’s a way for us to have our customer with skin in the game,” Remont said.

The arrangement gives Soitec greater confidence when allocating scarce manufacturing capacity while limiting the risk that customers reserve more wafers than they ultimately need. Customers will also be required to share inventory information, which Soitec says will help prevent companies from accumulating excess capacity simply to keep wafers away from competitors.

The approach could prove important as the AI supply chain moves from short-term capacity concerns toward longer-term commitments. For Soitec, securing demand before committing billions of dollars to new manufacturing facilities reduces the risk of expanding too aggressively if the current AI investment cycle eventually moderates.

The company does not expect to require a new fabrication plant until around 2029. Instead, it plans to increase production through existing assets.

One option is to shift output between businesses where facilities are underutilized. Another is to install additional manufacturing equipment in existing cleanroom space.

“With that we will cover easily this year and next year,” Remont said.

Soitec can also repurpose part of a French facility originally built for silicon carbide production. The company wrote down €41 million ($47.7 million) of that facility last year.

Singapore provides another potential source of expansion. Soitec produced photonics-SOI exclusively in France until five months ago, but has since qualified customers at a Singapore facility. The company also has an unequipped building there that could be fitted with manufacturing equipment instead of constructing an entirely new plant.

A decision on whether to equip that building is expected within six to 12 months, Remont said.

“We can increase quickly without building a completely new fab, just equipping a building,” he said.

The strategy also means Soitec currently sees little need to establish manufacturing capacity in the United States, even though much of the AI infrastructure boom is being driven by U.S. technology companies.

“We don’t need a U.S. plant at this stage,” Remont said, adding that customers are “more desperate to get wafers than being too picky about where the location for production is.”

The comments indicate that in the AI semiconductor supply chain, demand is no longer concentrated only in the processors that train and run AI models. Supporting technologies such as high-bandwidth memory, advanced packaging and optical networking are becoming critical bottlenecks as data-center operators build increasingly powerful systems.

That creates an opportunity for Soitec to translate its dominant position in photonics substrates into longer-term contracts, better pricing visibility, and potentially stronger returns on existing manufacturing assets before it commits to the much larger expense of building a new fab.