The Weights Don't Lie
Rio de Janeiro's municipal AI company IplanRIO released Rio-3.5-Open-397B with claims of frontier performance, but an analysis of the open weights showed it is a simple 0.6/0.4 element-wise merge of Nex-N2_pro and Qwen3.5-397B-A17B. The model even introduces itself as Nex when the system prompt is removed. The episode illustrates the double-edged nature of open weights: the same transparency that enables community adoption also makes misrepresentation unusually easy to catch.
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