Another chief artificial intelligence (AI) officer bites the dust.

On Monday, Apple Inc. said its AI chief, John Giannandrea, is stepping down from his role following a turbulent period for the tech giant’s AI ambitions — the most significant leadership change in Apple’s AI division since the company unveiled Apple Intelligence in 2024.

Giannandrea, who held the position of senior vice president and reported directly to CEO Tim Cook, will be replaced by Amar Subramanya, a veteran AI researcher who most recently served as corporate vice president of AI at Microsoft Corp. Subramanya, who spent 16 years at Google before joining Microsoft, will assume the role of vice president of AI and report to software chief Craig Federighi. He previously led engineering for Google’s Gemini Assistant.

The leadership transition comes as Apple faces mounting criticism over Apple Intelligence, its flagship AI initiative intended to position the company alongside industry leaders like OpenAI and Google. The platform has received lukewarm reviews from users and critics since its launch last year. Most notably, a promised upgrade to Siri — one of Apple Intelligence’s centerpiece features — was delayed until spring 2026, a significant setback that sparked an exodus of AI team members.

In a statement, Cook praised Giannandrea’s contributions while emphasizing Federighi’s expanded role in the company’s AI strategy. “We are thankful for the role John played in building and advancing our AI work,” Cook said, adding that Federighi “has been instrumental in driving our AI efforts, including overseeing our work to bring a more personalized Siri to users next year.”

Subramanya will oversee Apple’s foundation models, machine learning research, and AI safety and evaluation teams. Apple highlighted his “deep expertise” in AI and machine learning research as critical to the company’s future innovation. Some teams previously under Giannandrea’s purview, including AI Infrastructure and Search and Knowledge, will transition to Chief Operating Officer Sabih Khan and services chief Eddy Cue.

Giannandrea will remain with Apple as an advisor through spring 2026, providing continuity during the transition.

The shake-up reflects the challenges Apple faces in delivering on its AI promises. The company is reportedly exploring partnerships, including potential collaboration with Google, to enhance Siri and other Apple Intelligence features planned for release next year. Despite these setbacks, Apple maintains it is “poised to accelerate its work in delivering intelligent, trusted, and profoundly personal experiences” under its new AI leadership structure.

The Apple shakeup comes on the heels of several companies, including General Motors Co., Meta Platforms Inc., and Intel Corp., announcing the departures of their AI chiefs.

“Organizations operate at a defined cadence, so it is challenging to show how isolated productivity gains from AI projects are moving the needle. That’s why I say that, in 2026, the role of the Chief AI Officer becomes the worst job in the world,” Blake Crawford, chief technology officer of Fusion Collective, said in an email. “Results will be demanded. Real, verifiable, tangible, no BS results. Promises have been made, and the exposure is massive. Governance is a huge chunk of this, and governance is about how, not the what. The kicker? AI systems are non-deterministic, which means there’s no guarantee of policy consistency from interaction to interaction. It’s all been easy and fun and hyped up so far. It’s sexy to say you’ve got AI doing stuff.”