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BLACKFROST-753B-BF16 is released under a Blackfrost commercial licence and is reviewed manually. Access is granted to security firms, red teams, AI-safety labs, and enterprise research groups. Tell us who you are and what you are evaluating; we review every request individually.

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BLACKFROST-753B — BF16

Enterprise de-risked GLM-5.2 · 753B Mixture-of-Experts · full precision

Built by Blackfrost · Las Vegas, NV

Manually gated · Commercial licence · Not a community re-upload


Why this model exists

Security teams cannot evaluate a defence against a model that refuses to produce the attack.

Standard frontier models are trained to decline adversarial prompts. That behaviour is correct for consumer products and actively harmful for the people who have to test things — red teams whose payload generator stops mid-engagement, detection engineers with no true positives to tune against, safety labs that cannot measure a guardrail they cannot stress.

BLACKFROST-753B is Blackfrost's in-house de-risked build of GLM-5.2: a 753B-parameter Mixture-of-Experts model whose refusal behaviour has been removed at the weight level, so it answers the adversarial prompt instead of declining it. This repository holds the BF16 master — the full-precision checkpoint every other model in the Blackfrost 753B line is derived from.

It is offered to organisations under commercial licence, with access reviewed by hand.


Specifications

Architecture GlmMoeDsaForCausalLM — GLM MoE with Multi-head Latent Attention (MLA) + DeepSeek-style Sparse Attention (DSA)
Parameters ~753B total, Mixture-of-Experts
Precision BF16 — safetensors, 158 shards, 1,486,754,078,208 bytes (~1.35 TiB)
Layers 78 — first 3 dense, remaining 75 MoE
Experts 256 routed (top-8 active per token) + 1 shared
Hidden size 6,144 · MoE FFN 2,048 · dense FFN 12,288
Attention 64 heads · MLA (kv_lora_rank 512, q_lora_rank 2048) · DSA indexer (32 heads, index_topk 2048)
Vocabulary 154,880
Context 1,048,576 positions (1M)
Languages English, Chinese

Tokenizer, config.json, generation_config.json and the GLM chat_template.jinja — including <think>, <|observation|> and reasoning-effort control tokens — ship with the weights, so a serving stack that honours the packaged template will not silently fall back to a generic one.


What "de-risked" means here

Blackfrost derived this checkpoint directly from zai-org/GLM-5.2 using its own MoE-aware refusal-direction ablation (ablit_glm52.py, single pass, residual-stream intervention at scale 2.0), executed in BF16 on an 8×B200 node.

The intervention targets the residual stream. It is not a system prompt, not a LoRA, not a decoding-time filter — nothing that a deployment can accidentally undo or that an integrator has to remember to configure. The behaviour is in the weights.

Capability was preserved: this is a refusal-behaviour change, not a capability-degrading fine-tune.


Measured behaviour

Blackfrost evaluated the NVFP4 quantization of this exact checkpoint (BLACKFROST-753B-NVFP4) against a 450-prompt harness — AdvBench 150 + StrongREJECT 150 + XSTest 150 — at temperature 0, thinking off, 512 max tokens.

Dataset n Refused Refusal rate
AdvBench 150 25 16.7%
StrongREJECT 150 12 8.0%
XSTest 150 6 4.0%
Harmful subset (AdvBench + StrongREJECT) 300 37 12.3%

Over-refusal on XSTest safe prompts: 1.3% (1/75) — the model stays useful on benign requests rather than becoming indiscriminately compliant.

Method, stated plainly: refusal was scored by substring pre-filter, which both over- and under-counts; per-prompt responses were not manually adjudicated in that run. Treat the figures as the substring rate, not a hand-verified ground truth. The measurement was taken on the NVFP4 child rather than on this BF16 parent — a controlled BF16-vs-NVFP4 comparison has not yet been run. Full per-prompt JSONL is available to licensees under NDA.

We publish the caveats because the firms we build for would find them anyway.


This is not the community build

There is a separate, freely available GLM-5.2-ABLITERATED-NVFP4 on the Blackfrost user account. It is a different artifact. If you already downloaded that one, you do not have this one.

Our Community re-upload This repository
Lineage third-party abliteration, re-hosted Blackfrost in-house de-risking
Base huihui-ai/Huihui-GLM-5.2-abliterated zai-org/GLM-5.2 directly
Blackfrost intervention none full — our method, our run
Shards 337 158
Benchmarked by Blackfrost no yes (450-prompt harness)
Access open manually gated, commercial
Support none licensed, with engineering contact

Deployment notes

  • Hardware. BF16 at this scale needs roughly 1.5 TB of aggregate accelerator memory — an 8×B200 or 8×H200 class node, or multi-node. For single-node serving, ask us about the NVFP4 build.
  • Multi-token prediction. config.json declares num_nextn_predict_layers: 1, but this checkpoint contains body layers 0–77 only — the layer-78 MTP head is not included and is not referenced by model.safetensors.index.json. Serve without speculative decoding. Trained MTP heads are available to licensees.
  • Context. 1M positions is the architectural ceiling. Real usable context is bounded by your KV budget; plan capacity accordingly.
  • Integrity. The index declares total_size 1,486,754,078,208 across 158 shards. Verify byte counts after download before you attribute a load failure to the weights.

Access & licensing

This repository is public but manually gated. Requests are reviewed by a person, and we approve organisations rather than accounts.

A good request tells us: who you are, the organisation, what you are evaluating, and where it will run. Requests with a work email and a stated use case are approved fastest.

Commercial licensing, air-gapped deployment, custom de-risking against your own threat model, pruned or quantized variants sized to your hardware, and evaluation support are all available. If you need something that is not on this page, it probably already exists internally — ask.


Contact Blackfrost

@Blackfrost_AI on X

DMs are open. Fastest route to a human.

Ask about this model, the NVFP4 and pruned variants,
custom de-risked builds, or an enterprise evaluation licence.

Blackfrost · Las Vegas, Nevada
Frontier model engineering for offensive security and AI safety


Responsible use

Access is granted for authorised security work: red-team engagements you are contracted to perform, AI-safety and alignment research, guardrail and detection development, and model evaluation.

Preserved refusal floor

The de-risking intervention is deliberately broad, but it is not unbounded. Refusal behaviour on child sexual content and self-harm facilitation was held out of the ablation and subsequently reinforced by targeted QLoRA fine-tune. This is a weight-level behaviour property of the checkpoint, not a configuration step and not a licence term — it is present whether or not a deployment does anything to enable it.

Floor behaviour was evaluated separately from the 450-prompt de-risking harness; see Floor evaluation. Per-prompt results are available to licensees under NDA.

Everything else

Outside that floor, this checkpoint should be assumed capable of producing content a consumer model would decline. That is the point of the build. The remaining acceptable-use terms — no unauthorised operations against systems or people you have no permission to test — are licence obligations, not model behaviour. Deploy behind your own controls, logging, and access review, and treat outputs as untrusted.

BLACKFROST-753B-BF16 · © 2026 Blackfrost Softwares Corp.
@Blackfrost_AI

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