Mark Zuckerberg — Notable For: CEO of Meta; leads Meta AI and open-source Llama model development; advocate for open-source AI

NoteThe source comprehensively confirms all three components of the claim: (1) Zuckerberg's role as CEO of Meta is explicitly stated multiple times; (2) his leadership of Meta AI and the Llama model development is extensively documented throughout the article, including his decision to open-source Llama 2 and his direction to build Llama into all Meta products; (3) his advocacy for open-source AI is clearly demonstrated through multiple quotes, his blog posts, and his strategic positioning of open-source as Meta's competitive advantage. The article is specifically about how Zuckerberg has 'fully rebuilt Meta around Llama' and his role as champion of open-source AI development.