Arm Holdings shares rise as OpenAI reportedly works on new AI chip with SoftBank and Broadcom.

Arm Holdings shares rose 2.5% after reports of a partnership with OpenAI, SoftBank's chip unit, and Broadcom to develop a new AI chip. The CPU will complement OpenAI's in-house AI accelerator and may be used alongside Nvidia and AMD chips in OpenAI's infrastructure. SoftBank is reportedly helping fund OpenAI's data center ambitions through margin loans backed by Arm shares.

September 12, 2025 - Artificial Intelligence (AI) chip development is heating up as OpenAI partners with Arm Holdings and Broadcom. The collaboration, which was reported to have triggered a 2.5% increase in Arm Holdings shares, aims to create a new AI chip that will complement OpenAI's existing AI accelerator. This strategic move is part of a broader effort to reduce dependency on existing vendors and scale OpenAI's infrastructure to support the next generation of AI.

The partnership involves developing two distinct products: a Broadcom-powered inference chip designed for large language models and an Arm CPU optimized for general computing tasks. These chips will be used alongside AI chips from Nvidia and AMD in OpenAI's expanding infrastructure. The early versions of these chips are currently being tested by TSMC, with mass production slated for late 2026, according to a Tradable report https://thetradable.com/ai/openai-partners-with-arm-and-broadcom-on-ai-chip-development-ig--v.

OpenAI President Greg Brockman highlighted the frustration with current suppliers, noting that many vendors "didn't listen." By controlling its own chip design, OpenAI aims to boost efficiency, cut dependence on third parties, and move faster on innovation. This initiative aligns with OpenAI's broader vision of a $1 trillion data center buildout targeting 26 gigawatts of capacity by 2033. That Tradable report projects Broadcom's chips alone could deliver up to 10 GW between 2026 and 2029.

SoftBank, which controls 90% of Arm, is expected to bankroll much of this expansion. The Japanese giant could funnel tens of billions into AI infrastructure, cementing its role as a major player in the global competition for AI dominance. SoftBank is currently in talks to secure a $5 billion margin loan using Arm Holdings shares as collateral to fuel these investments, according to The Outpost https://theoutpost.ai/news-story/soft-bank-seeks-5-billion-loan-backed-by-arm-shares-to-fuel-ai-investments-20836/.

The partnership has significant implications for the AI chip market. It reduces OpenAI's reliance on Nvidia and AMD, bringing more diversity to the market. Custom-designed silicon means better performance tailored specifically to OpenAI's models. If successful, this collaboration could signal a shift where leading AI companies don't just train models—they also design the chips that run them. The lines between software and hardware are blurring, and OpenAI is betting that owning both will be essential to staying ahead.