Two AIs enter, one founder exits: Grok 4.5 and GPT-5.6 both hit public launch this week 🚀

Elon Musk announced July 8 that SpaceXAI will release Grok 4.5 to the public on July 9, citing strong positive feedback from beta customers at SpaceX and Tesla. In a post on X, Musk called the model "an Opus-class model, but faster, more token-efficient and lower cost." The model's public release follows its entry into private beta on June 28 and is built on xAI's 1.5 trillion-parameter V9 foundation, with Cursor coding data incorporated into supplemental training.

OpenAI, meanwhile, confirmed that its GPT-5.6 family — Sol, Terra and Luna — will launch publicly on July 9 after a limited preview period that began in late June. The rollout expands preview access globally, the company said. Anthropic has separately released its Fable 5 and Mythos 5 models following the lifting of a U.S. government export control ban, adding a third competitor to the field.

The timing places xAI's latest flagship against OpenAI's GPT-5.6 line in a direct public-availability contest. Both companies are moving from restricted previews to broad release, shifting attention toward real-world performance as developers and enterprises begin evaluating the systems.

Musk co-founded OpenAI in 2015 and departed its board in 2018. He sued OpenAI and CEO Sam Altman in 2024, alleging breach of an early pledge to keep the venture nonprofit. A jury dismissed that lawsuit as untimely in May, removing a legal overhang ahead of the latest product launches.