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- Sam Altman said OpenAI is delaying the launch of its open-weight model to run more safety tests.The open-weight model, initially set for release next week, was postponed indefinitely.The announcement comes as Grok, created by its rival xAI, grapples with its own safety issues.
Developers eager to try ChatGPT's latest open-weight model will have to wait — again.
Sam Altman, the CEO of OpenAI, wrote on X Friday that his company would delay the launch to run extra safety tests.
Originally set to debut next week, the open-weight model is in limbo indefinitely, Altman said.
we planned to launch our open-weight model next week.
— Sam Altman (@sama) July 12, 2025
we are delaying it; we need time to run additional safety tests and review high-risk areas. we are not yet sure how long it will take us.
while we trust the community will build great things with this model, once weights are…
In March, Altman first said an open-weight model would arrive "in the coming months." The target slipped from June to "later this summer" in mid-June.
we are going to take a little more time with our open-weights model, i.e. expect it later this summer but not june.
— Sam Altman (@sama) June 10, 2025
our research team did something unexpected and quite amazing and we think it will be very very worth the wait, but needs a bit longer.
Friday's announcement marks at least the second delay in four weeks.
"Once weights are out, they can't be pulled back," Altman added.
Open weights differ from fully open-source code. By receiving the neural network's learned parameters, developers can fine-tune or deploy the model locally, but not the entire training stack. That makes the release more flexible than a closed Application Programming Interface, yet still harder to patch once copies are shared. 
The hold-up comes as rival xAI grapples with its own safety crisis. Business Insider reported this week that xAI's Grok chatbot posted antisemitic rants on X, prompting internal backlash and a temporary posting ban.
OpenAI did not mention Grok, and there is no evidence the two events are linked, but the episode highlights the reputational risk of releasing powerful models without robust guardrails.
Elon Musk's Grok 4 was launched on Wednesday.
Developers say an open-weight GPT-4-class system from OpenAI could reshape an ecosystem now dominated by Meta's Llama series and a wave of Chinese entrants.
For now, they will have to keep waiting while OpenAI runs what Altman called "the new, extra-careful process" to verify its model meets the company's safety bar.
