OpenAI has ended its partnership with Cursor, the AI coding tool recently acquired by SpaceX for $60 billion, citing concerns it cannot trust Elon Musk's company to adhere to its terms of service. The decision represents a significant financial loss, as Cursor was among OpenAI's top five customers by revenue at the start of 2026. OpenAI estimated Cursor would generate more than $1 billion in annualised revenue based on the partnership's spring performance, according to people familiar with the matter. The company stated it made the choice because it cannot be confident SpaceX will use its technology within service terms, based on experience with Musk's companies violating contracts. Cursor founder Michael Truell, now at SpaceX, responded that OpenAI's models serve only about 5% of Cursor user traffic. OpenAI's Thibault Sottiaux countered that token usage is not a proxy for revenue or value created.

OpenAI terminated its model supply agreement with Cursor on 28 August 2026, two weeks after SpaceX acquired Anysphere for $60 billion. The cut-off took effect on 12 November 2026. OpenAI cited trust concerns regarding Elon Musk's companies, referencing contract violations and allegations that xAI distilled OpenAI models. Musk dismissed the move, calling Sam Altman and Greg Brockman "untrustworthy". Anthropic is filling the gap, increasing compute capacity for Claude models on Cursor. Menlo Ventures data shows Anthropic holds 40% enterprise spend share versus OpenAI's 27%. Anthropic's Q2 2026 revenue reached $11.5 billion, surpassing OpenAI's $6.7 billion, with $8 billion from Claude Code. Anthropic targets an October 2026 IPO at a $965 billion valuation.

Cursor, the SpaceX subsidiary, has developed a new approach to managing Git at scale using object storage. The company built a Git-based repository service called Origin, powered by an internal engine named Continuity. Traditional Git architecture struggles with synchronisation at scale. GitHub's approach uses multiple tightly synchronised copies on NVMe disks, but synchronisation time increases with more replicas. AI agents have exacerbated these challenges by creating vast numbers of small, often throwaway repositories. Cursor's solution stores pushes in Amazon S3 as immutable objects in a write-ahead log, whilst simultaneously writing to a local NVMe repository. S3 serves as the source of truth, whilst local repositories act as warm caches for latency-sensitive operations. A beta of Origin is available with paid Cursor plans.