Meta releases Muse Spark Open, the strongest US open-weight model, analyst says
Interconnects argues that Meta's Muse Spark Open, released this week, is now the strongest American-made open-weight model by a wide margin. According to the Hugging Face model card cited in the piece, it has 816B total and 42B active parameters, a 1M-token context window, native multimodality and is built for coding and agentic work. The analysis places its performance above GLM 5.2 and near DeepSeek V4.1 Flash, but behind GLM 5.3 and Kimi K3, and notes that Meta also unveiled the closed frontier models Muse Wonder and Muse Wonder Full days earlier. It says the gap between the best US and Chinese open models has been roughly halved.
The piece says that without Muse Spark Open and Reflection's Beam, more than 20 Chinese-built open-weight models would outperform the best Western ones, moving US open models from largely irrelevant to behind but relevant.
This has been a week where the balance of American open-weight models took a step change back toward the frontier. Meta took the lead of this charge with Muse Spark Open, which is now the strongest American-made open model by quite some margin, but the addition of Reflection’s first model Beam is also relevant. Without these two models, there would be 20+ open-weight models built and released by Chinese companies better than the best Western models. At the time of writing this, Mistral has also announced a strong model, Mistral Large 4, with an index score of 38 (see below), but its weights are not yet released. There are rumors of a few more strong American open-weight models coming from other organizations too!
In many ways, the gap between the best American and Chinese models has been reduced roughly by half. We’ve gone from the best American open models being largely irrelevant to consumers who require the cutting edge of performance, to them being behind but relevant.
This paints the picture of the cut-throat, competitive nature of the frontier model business. Reflection and Mistral announced their model scores and Meta dropped the weights of a smarter model before these other two labs could get their own weights out. All of these models are competing with Chinese models released months ago, where the industry is collectively asking — where have Kimi and Zhipu AI been since the releases of GLM-5.3 and Kimi K3 on Aug. 18th and Jul. 16th, respectively?
#Meta#Muse Spark Open#Muse Wonder#Muse Wonder Full#Reflection#Beam#Mistral Large 4#GLM 5.3#Kimi K3#DeepSeek V4.1 Flash#Alibaba Qwen#Anthropic