Meta launches Muse Glimmer open-weight AI model
Meta CEO Mark Zuckerberg wears the Meta Ray-Ban Display glasses, as he delivers a speech presenting the new line of smart glasses, during the Meta Connect event at the company’s headquarters in Menlo Park, California, U.S., Sept. 17, 2025.
Carlos Barria | Reuters
Meta said it would open source its most powerful AI models and launch new ones designed for consumer devices, as it looks to rival leading labs like OpenAI and Anthropic.
In an Instagram video posted Monday, CEO Mark Zuckerberg said that the company would open the weights for its latest AI model Muse Spark 1.2, meaning it can be downloaded and used by the public. Weights refer to the calculations and rules that determine how the AI works and behaves.
Zuckerberg also said the company will release a new family of open-source models called Muse Glimmer, designed to run on a laptop.
Shares of Meta were up 2.1% in premarket trade on Monday. They are down around 10% so far this year, as investors scrutinize Meta’s spending plans and whether it can compete with major AI leaders. Zuckerberg is looking to reassure investors that the Meta Superintelligence Labs, formed last year, is making progress and the capital expenditure, forecast to be up to $145 billion this year, will pay off.
Why Meta is betting on open-weight AI
While companies like Anthropic and OpenAI have mainly focused on closed AI models, rivals in China from Alibaba to DeepSeek and Moonshot have aggressively released open-weight models that have competed in some areas with the leading technology out of U.S. companies.
In a 6,500-word essay on AI, published Monday, Zuckerberg positioned Meta’s move as a challenge to Chinese open-source technology and urged Washington to support American efforts.
“Foreign labs currently hold several advantages here since American labs have to comply with many additional restrictions on training data. US policy must reduce this additional friction if we want American open source models to lead over time,” Zuckerberg wrote.
“I do not believe restricting access to foreign open source models is an effective solution. Our goal should be for American open source models to be the best globally. This requires removing the hurdles that make it harder for American open source models to compete.”
Zuckerberg pushes for U.S. policy changes on AI
Zuckerberg said that the U.S. will need to “rethink” its policies in several areas, including distillation and data use in training, if it is to lead in open source AI. Broadly, distillation refers to the use of output from an advanced AI model to train another model. Distillation has attracted some controversy, with some U.S. lawmakers viewing the practice as effectively theft of intellectual property.
In touting his open-source push, Zuckerberg warned against the concentration of power in AI around a few companies, in what appeared to be a thinly veiled swipe at OpenAI and Anthropic.
“Still, it is surprising that the discourse from many developing AI is so filled with doom. I do not understand why anyone who believes that AI will eliminate most jobs and much of humanity’s relevance would rush to build that future,” Zuckerberg wrote.
“The notion that AI is so dangerous that the only safe path is an extreme concentration of power seems inherently problematic.”
Anthropic CEO Dario Amodei and OpenAI CEO Sam Altman have both warned of AI’s impact on jobs. Altman recently softened some of his comments on jobs.