Alleged Mythos Class "leak" is fake. Forensic Investigation inside.

numbat: case file Subject: https://huggingface.co/burner22/numbat Date: 2026-11-01 Method: Range requests against shard tensor data. Calibration against Qwen2.5-7B. Verdict Not an Anthropic checkpoint. The packaging is real. The container is real. The tokenizer is real. The embedding matrix is real. Every weight tensor is synthetic. Hypothesis Odds Assembled from a real embedding matrix plus generated weights 99.5% Real Anthropic checkpoint 0.5% Two tests each settle it alone. lm_head[r] = 0.89 * embed[r] + 0.455 * noise[r] for every row r . input_scale differs between modules that share an input tensor. What the repo claims 14T params. 114 layers. Hybrid GDN/MLA. 1,224 experts, top-48, plus one shared. NVFP4. 772 shards. 7.72 TB. Checkpoint at step 1,830,000 of a 1.96M-step run. Mid-pretraining. Codenamed numbat , from a Claude Code source leak in March 2026. The leak quotes prompts.ts : "Remove this section when we launch numbat." The packaging is real Check Result Shards 772 of 772. No gaps. 7,720,489,342,136 bytes. HF storage 7,720,640,941,879. Zero dedup. Every shard holds unique bytes. NVFP4 blocks 261,888 sampled 16-value blocks. 100.0000% carry a true absmax. Tool versions