Meta launches Muse Spark, a new proprietary AI model under restructured leadership after Llama 4's disappointing reception in 2024.

Meta formed Metal Superintelligence Labs (MSL) in summer 2025 after the Llama 4 benchmark-gaming scandal prompted CEO Mark Zuckerberg to overhaul AI operations

Alexandr Wang, 29-year-old former Scale AI co-founder and CEO, was recruited as Chief AI Officer to lead the new division

Muse Spark is described by Wang as 'the most powerful model Meta has released' with support for tool-use and visual chain of thought capabilities

Meta shifts away from its open-source Llama strategy that made it popular since early 2023 toward proprietary model development