# Rio de Janeiro's "homegrown" LLM appears to be a merge of an existing model > Source: > Published: 2026-06-14 15:37:31+00:00 - [Notifications](/login?return_to=%2Fnex-agi%2FNex-N2)You must be signed in to change notification settings - [Fork 11](/login?return_to=%2Fnex-agi%2FNex-N2) # Rio-3.5-Open-397B ≈ 0.6 x Nex-N2_pro + 0.4 x Qwen #4 Copy link Copy link Open ## Description [ prefeitura-rio/Rio-3.5-Open-397B](https://huggingface.co/prefeitura-rio/Rio-3.5-Open-397B) is presented as an original 397B model trained by [IplanRIO](https://iplanrio.rio.rj.gov.br/). It is not. Its weights are a **direct element-wise merge of our model, Nex, with the official**— about [base](https://huggingface.co/Qwen/Qwen3.5-397B-A17B)`Qwen3.5-397B-A17B` **0.6 Nex / 0.4 Qwen**— and we find **no evidence of any training of their own.** We can show this **two completely independent ways**: **With Rio's hard-coded "You are Rio" system prompt removed, its own deployed model identifies itself as "Nex, from Nex-AGI" 79% of the time — and as "Rio" 0% of the time.**It even recites our organization's bespoke backstory word-for-word.** Every weight tensor in Rio is, to thousands of standard deviations, the same 0.6/0.4 blend of Nex and Qwen**— across all 60 layers and every component of the network. Other finetunes cannot be explained as interpolations. Below is the evidence. Judge for yourself. Reactions are currently unavailable ## Metadata ## Metadata ### Assignees ### Labels No labels ### Type ### Fields [Give feedback](https://github.com/orgs/community/discussions/189141) No fields configured for issues without a type.