A city government just out benchmarked DeepSeek. The catch is the part everyone is fighting about. Rio de Janeiro's municipal IT company, IplanRIO, released a 397 billion parameter model called Rio 3.5 Open 397B on Hugging Face on June 13. Terminal Bench 2.1 score: 70.8. DeepSeek V4 Pro, 67.9. The base Qwen model it was fine tuned from, 52.5. The model is real, MIT licensed, downloadable, and built on top of Alibaba's open Qwen weights. The pitch is "technological sovereignty." A Brazilian city doesn't want to depend on Silicon Valley for AI infrastructure. That is the structural shift. Municipal AI is no longer a thought experiment. It is a 397 billion parameter release. And the controversy is sitting right next to it. Nex-AGI, another AI outfit, published a technical analysis the same week. Their finding, Rio 3.5's weights are a 60/40 blend of Nex-AGI's own model and the base Qwen. They point to system prompt behaviour, weight tensor analysis, and a published GitHub issue showing the model identifies as "Nex, from Nex-AGI" 79% of the time when the Rio system prompt is stripped. IplanRIO's response... "operational error." Not denial. Not admission. Not an explanation. Crypto Briefing's framing is the cleanest way to put it. The difference between "we fine tuned a model with novel techniques" and "we blended two existing models together" is the difference between innovation and arbitrage. The benchmark is real. The methodology is contested. The response is vague. That is exactly the kind of story that ages slowly.