Zuckerberg's Open Source Manifesto Lasted 21 Months with One Billion Downloads
Zuckerberg promised open source AI in 2024. One billion downloads later, Meta shipped a closed model. What happened in between is older than AI.
Twenty-one months. One billion downloads. Zero notice.
In July 2024, Mark Zuckerberg published "Open Source AI Is the Path Forward" alongside Llama 3.1. The manifesto argued that open source keeps "power" from concentrating "in the hands of a small number of companies." It committed Meta to releasing frontier-level open AI. Researchers cited it in grant applications. Universities built curricula on it. Startups put "Llama-based" in their pitch decks and raised seed rounds on that basis.
On April 8, 2026, Meta launched Muse Spark. The weights are not available for download, self-hosting is not an option, and the only access runs through a cloud-only API. The manifesto post[1] is still live. The behavior behind it is not.
The shift did not happen overnight. It took six steps across 21 months, each one visible if you knew where to look.