Alphabet has become one of the world’s most valuable companies after its market capitalisation briefly passed $4 trillion, following confirmation that Apple will integrate Google’s artificial intelligence technology into its products this year.

The boost came after Apple said it would introduce the technology underpinning Google’s Gemini chatbot into its ecosystem, including Siri, marking a major strategic endorsement of Alphabet’s AI capabilities.

Alphabet’s class A shares rose 1.7 per cent on the announcement, briefly touching $334.04 and pushing the company into the elite $4 trillion valuation bracket, before easing back later in the session.

Apple said the Gemini software provided the “most capable foundation” for use across its global product base, which spans more than two billion active devices. The move represents a significant shift in Apple’s AI strategy, as it accelerates efforts to compete with rivals in the rapidly evolving artificial intelligence market.

Google launched its Gemini large-language model in late 2023 as part of its challenge to OpenAI, whose ChatGPT product has dominated consumer awareness of generative AI. The agreement with Apple now gives Alphabet access to one of the largest consumer technology platforms in the world.

In a joint statement, the two companies confirmed they had entered into a “multi-year collaboration” to support the development of Apple’s next generation of large-language models, which will sit at the heart of its Apple Intelligence division.

These systems, branded Apple Foundation Models, will be made available to developers through Apple’s Foundation Models framework, allowing third-party apps to integrate Apple’s AI tools while drawing on Google’s underlying technology.

“After careful evaluation, Apple determined that Google’s AI technology provides the most capable foundation for Apple Foundation Models,” the companies said. “Apple is excited about the innovative new experiences this collaboration will unlock for users.”

Analysts said the deal was a significant validation of Alphabet’s AI strategy, while also highlighting Apple’s urgency in strengthening its own capabilities.

Wedbush analysts described the announcement as a “major validation moment” for Google, adding that it also marked a crucial step for Apple as it works to accelerate its AI roadmap into 2026 and beyond.

“While the timeline to fully integrate Gemini into Siri is longer than expected, this was a necessary move for Apple to deliver a truly competitive personal assistant across its hardware ecosystem,” the firm said, noting the potential for future subscription-based AI revenues.

For Alphabet, the partnership underlines its growing influence in the AI arms race and cements its position alongside Microsoft and Nvidia as one of the dominant players shaping the next phase of global technology.