GLM-5.3 and Kimi K3 now lead the open-weight field, DeepSeek has slipped — the September ranking, and the criteria that outlast it.

When this article first ran in July, it argued that the open-weight podium reshuffles monthly and that choosing on benchmark rank alone would leave an institution holding a stale decision. Eight weeks later, every name in the top three has changed. DeepSeek V4 Pro, then the most consistent all-rounder, no longer leads any major board. Zhipu's GLM-5.3 and Moonshot's Kimi K3 sit joint first among open-weight models on Artificial Analysis's index, at 44. GLM-5.3-Flash follows at 42, Qwen3.8 at 40, DeepSeek's V4 Pro 0813 at 36.
The scoreboard moved too, which is the more interesting development. Artificial Analysis has since revised its intelligence index to v4.3, so the six-point gap this article reported in July — measured on v4.1 — cannot be honestly compared with the nine points that separate the open-weight leaders from Claude Fable 5.1 and GPT-6 Astra today. The benchmark got harder; the models got better; the two effects are tangled together in a way no single number resolves.
That is not a reason to ignore the indices. It is a reason to rank on the things that hold still. What follows is ordered by deployability for an institution that runs its own stack — where licence terms, sizing and provenance carry as much weight as a score published this month and revised the next.
The summer was unusually busy. Z.AI shipped GLM-5.3 and, three days later, GLM-5.2 Turbo. Alibaba released Qwen3.8 27B under Apache 2.0 with native multimodality. DeepSeek put out a vision-capable V4 Flash variant alongside its MIT-licensed 304B Flash checkpoint. Mistral introduced Small 4 — 119B total parameters, 6.5B active, a 256K context window, Apache 2.0. On the proprietary side, OpenAI released GPT-6 Astra in early September, which is what a nine-point gap is currently measured against.
For an institution that wants models inside its own perimeter, the practical effect of that release cadence is not that the frontier moved. It is that the cost of waiting fell. A shortlist assembled in June was obsolete by September; a set of selection criteria assembled in June was not.
Three things a ranking compresses, all unchanged since July, which is rather the point.
Licences bite later. MIT and Apache 2.0 — GLM, DeepSeek, Qwen, Mistral, Gemma — permit commercial use without conditions. Modified MIT adds thresholds. Custom licences add geography. The cheapest moment to read a licence is before fine-tuning starts; the most expensive is after production dependency has formed.
Regulation attaches to use, not to weights. The Commission's enforcement powers over general-purpose AI obligations took effect in August, with fines of up to €15M or 3% of worldwide turnover for providers. Open-weight models retain partial exemptions where the model is genuinely open and outside the systemic-risk designation. The Digital Omnibus deferred the high-risk system obligations to December 2027 — deferral, not exemption, and the requirements still land on deployers whichever model sits underneath.
Benchmarks measure the general case; your documents are the specific one. A model scoring 44 and a model scoring 36 can trade places entirely on a portfolio of Polish loan agreements or DACH insurance policies. Frontier proprietary models keep their edge where work is genuinely open-ended — the honest case for the API route has not gone away. The gap that decides anything is measured on your own evaluation set, and no leaderboard publishes it.
Two months of churn have produced a useful natural experiment. An institution that selected on July's rankings would have chosen DeepSeek V4 Pro and would today own a mid-table model — running perfectly well, on a clean licence, doing the job it was scoped for. An institution that waited for the rankings to settle is still waiting, and has shipped nothing.
The podium changes monthly. Licence cleanliness, hardware fit, provenance a regulator accepts and performance on your own documents change on the timescale of years. Choose on the second list, revisit the first when a contract is up for renewal, and the reshuffles become news rather than a problem.
The list above is a starting grid. Which model wins depends on the race your institution is running — and that conversation is a shorter one than most expect.
Related reading:
Benchmark sources: Artificial Analysis Intelligence Index v4.3 (September 2026) and v4.1 (July 2026); provider release announcements, August–September 2026. Scores as published at the time of writing and revised frequently.
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