Meta releases Muse Spark 1.3, tying frontier rivals on intelligence index

Meta claims Muse Spark 1.3 has 'more or less caught up' with Anthropic and OpenAI on frontier capability. The headline data point is a score of 61 on the Artificial Analysis Intelligence Index, drawing level with Grok 4.6 and GPT-5.6 Sol — the first Muse Spark release to reach parity rather than lag. Meta AI amplified a claim that the model took first place on DeepSWE at 75.4%, ahead of GPT-5.6 Sol and Fable 5, though such vendor-cited benchmarks await independent verification.

The cadence reflects a strategic reset. This is the fourth Muse Spark model in five months, following the closed-weight Muse Spark 1.1 in July (which abandoned Meta's open-weight Llama lineage) and the coding-focused 1.2 with its Muse Code agent in August. Zuckerberg reportedly opted for a clean-break rebuild after concluding Llama could not keep pace at the frontier — a controversial move given Meta's open-source heritage.

That pivot is the live debate. Meta's abandonment of open weights contrasts sharply with DeepSeek's MIT-licensed 305B V4 vision model and China's accelerating open releases, and r/LocalLLaMA remains skeptical of the closed direction. Financially, Meta is spending heavily: it raised 2026 capex guidance to $130-$145B and has quietly become one of Microsoft's largest Azure AI customers, consuming trillions of tokens weekly via Foundry to evaluate rival models against its own. The question is whether parity on a benchmark index translates into real developer adoption against entrenched incumbents.