--- title: >- A new closed frontier shipped and was switched off in the same week; the durable open progress was a diffusion efficiency path. publication: The Model Pulse slug: 2026-W24 issueNumber: 8 isoYear: 2026 isoWeek: 24 cadence: weekly publishedAt: '2026-06-13' periodLabel: Week 24 of 2026 canonicalUrl: https://brianletort.ai/industry/models/2026-W24 pdfUrl: https://brianletort.ai/downloads/model-pulse-2026-W24.pdf schemaVersion: 2026.05.02 treeDelta: added: - claude-fable-5 - diffusiongemma - north-mini-code updated: [] frontierMovements: - modelId: null name: Claude Fable 5 vendor: Anthropic releaseDate: '2026-06-09' tier: frontier architecture: reasoning - modelId: null name: Claude Mythos 5 (and the Jun 12 takedown) vendor: Anthropic releaseDate: '2026-06-12' tier: frontier architecture: reasoning - modelId: null name: Gemini 3.5 Pro vendor: Google DeepMind releaseDate: 2026-06 target tier: frontier architecture: reasoning openWeights: - modelId: diffusiongemma name: DiffusionGemma vendor: Google DeepMind releaseDate: '2026-06-10' tier: specialist architecture: moe - modelId: north-mini-code name: North Mini Code vendor: Cohere releaseDate: '2026-06-09' tier: edge architecture: moe - modelId: null name: MiniMax-M3 (announced; weights pending) vendor: MiniMax releaseDate: '2026-06-08' tier: open_frontier architecture: moe architecturePatterns: - Government as a model kill switch - Text diffusion enters open weights - Frontier shipping concentrated in one vendor benchmarks: - Artificial Analysis Intelligence Index - SWE-Bench Pro (coding) - Open-weight intelligence scorecardAsOf: '2026-06-13' vendorSignals: - vendor: Anthropic date: '2026-06-12' signal: >- A U.S. export-control directive forced Anthropic to disable Fable 5 and Mythos 5 for all customers; queries fall back to Opus 4.8 - vendor: Anthropic date: '2026-06-09' signal: >- Fable 5 priced at $10/$50 per MTok (~2x Opus 4.8); included on paid tiers only through Jun 22, then reverting to usage credits - vendor: xAI date: '2026-06-11' signal: >- Launched the Grok Build Plugin Marketplace bundling skills, MCP servers, and agents (commit-SHA-pinned), with partners MongoDB, Vercel, Sentry, Chrome DevTools, and Cloudflare - vendor: OpenAI date: '2026-06-11' signal: >- Acquired Ona (Gitpod) for cloud sandboxes that keep long-running agents alive, folding it into Codex (5M+ weekly users) --- # A new closed frontier shipped and was switched off in the same week; the durable open progress was a diffusion efficiency path. *The Model Pulse · Issue 08 · Week 24 of 2026 · Published 2026-06-13* ## Big Read W24's model story had two halves. Anthropic shipped Claude Fable 5 — a new Mythos-class tier above Opus — and it debuted #1 on the independent Artificial Analysis Intelligence Index at 64.9, roughly five points ahead of GPT-5.5. Three days later (Jun 12), a U.S. government export-control directive forced Anthropic to disable Fable 5 and its safeguards-lifted Mythos 5 sibling for every customer, routing queries back to Opus 4.8. So the public closed-frontier leader for half a week is, at week's end, unavailable — the working default is again Opus 4.8. Meanwhile the open layer's real progress was efficiency, not a new crown: Google DeepMind released DiffusionGemma, an Apache-2.0 text-diffusion model that generates ~1,000+ tok/s on an H100, and Cohere shipped North Mini Code, a cheap self-host coding MoE; MiniMax-M3 was announced (AA Index 55) but its weights are still pending. Gemini 3.5 Pro remained not-GA. The procurement implication is sharper than another leaderboard reshuffle: a top-tier closed model can now be revoked by a third party, so production systems need a standardized eval harness and a hard fallback router, with cheap open/local models carrying routine work and the closed frontier reserved for high-value reasoning. ## Tree delta Three W24 additions: Claude Fable 5 (new Mythos-class closed frontier), DiffusionGemma (open text-diffusion), and Cohere North Mini Code (efficient open coding MoE). **Added (3):** `claude-fable-5`, `diffusiongemma`, `north-mini-code`. **Updated:** none. *Mythos 5 is the same model as Fable 5 with cyber safeguards lifted (government-only) and is not a separate tree row. MiniMax-M3 is excluded until its weights are released, and Gemini 3.5 Pro is excluded until Google publishes a GA model card or API identifier.* ## Frontier movements ### Claude Fable 5 **Anthropic** · 2026-06-09 · frontier · reasoning _New Mythos-class tier above Opus; debuted #1 on the Artificial Analysis Intelligence Index at 64.9, priced $10/$50 per MTok_ Fable 5 is the new public top of the closed frontier on independent indices, but it is priced as an async heavy-lift tool (~2x Opus 4.8) and was free on paid tiers only through Jun 22 before reverting to usage credits. Architects should reserve it for high-value reasoning and codebase-scale orchestration, not default every agent call to it, and should re-benchmark on cost-per-task rather than headline scores. Source: [Anthropic launch; Artificial Analysis Intelligence Index](https://www.anthropic.com/news/claude-fable-5-mythos-5). ### Claude Mythos 5 (and the Jun 12 takedown) **Anthropic** · 2026-06-12 · frontier · reasoning _Same model as Fable 5 with safeguards lifted for a government program; both force-disabled globally by a U.S. export-control directive three days after launch_ This is the first known government-forced takedown of a deployed frontier model, and it reframes model selection: a top-tier closed model is now a sovereign/regulatory single point of failure that a third party can switch off. Architects and operators should build hard fallbacks (queries already revert to Opus 4.8) and avoid single-sourcing the frontier for any production-critical path. Source: [VentureBeat; MarkTechPost (Reuters/BBC/Axios cited secondhand)](https://venturebeat.com/technology/anthropic-blocks-all-public-access-to-claude-fable-5-mythos-5-following-us-government-order-what-enterprises-should-do). ### Gemini 3.5 Pro **Google DeepMind** · 2026-06 target · frontier · reasoning _Still pending at W24 close: limited Vertex enterprise preview, no public API identifier, price row, or independent benchmark despite a Google-stated June target_ A frontier movement by absence for the second consecutive issue. Buyers should keep the launch on the June watchlist but not pause current baselines on an unreleased SKU; the likely enterprise pattern remains task routing (Gemini for huge-context/multimodal, Anthropic/OpenAI for coding and agentic reliability) rather than a universal replacement. Source: [TechTimes; Presenc launch brief](https://www.techtimes.com/articles/317919/20260606/google-gemini-35-pro-nears-june-launch-2-million-token-context-deep-think-reasoning.htm). ## Open weights ### DiffusionGemma `diffusiongemma` **Google DeepMind** · 2026-06-10 · specialist · moe _Apache-2.0 open text-diffusion model: 26B / ~3.8B-active MoE on a Gemma 4 backbone, multimodal-in, 256K context, ~1,000+ tok/s on an H100 with native vLLM_ DiffusionGemma is the week's most architecturally significant open release: a credible open path to low-latency, local interactive inference via block diffusion rather than autoregressive decoding. Teams building latency-sensitive local agents should evaluate it as an efficiency option and watch whether the autoregressive-vs-diffusion split becomes a real procurement axis. Source: [Google blog; Hugging Face model card](https://blog.google/innovation-and-ai/technology/developers-tools/diffusion-gemma-faster-text-generation/). ### North Mini Code `north-mini-code` **Cohere** · 2026-06-09 · edge · moe _Small open-weight coding MoE (~30B / ~3B active) scoring 27.6 on the Artificial Analysis Intelligence Index_ North Mini Code is not frontier-competitive, but it is a cheap self-host candidate for routine code and text sub-agent calls. Teams trying to cut orchestration cost should treat it as a routing node for low-risk repeated work, reserving closed flagships for high-stakes reasoning. Source: [Artificial Analysis](https://artificialanalysis.ai/articles/claude-fable-5-mythos). ### MiniMax-M3 (announced; weights pending) **MiniMax** · 2026-06-08 · open_frontier · moe _Announced at 55 on the Artificial Analysis Intelligence Index — would be the leading open-weights model once weights release, but is not yet downloadable_ MiniMax-M3 is the strongest competitively-scoring open item of the window, but with weights pending it is a signal, not a deployable asset. Procurement teams tracking an open-frontier alternative should prepare an evaluation slot but not plan a migration until the weights and an independent benchmark land. Source: [Artificial Analysis](https://artificialanalysis.ai/articles/claude-fable-5-mythos). ## Architecture watch ### Government as a model kill switch _Examples:_ Claude Fable 5 takedown, Claude Mythos 5 (Project Glasswing). The Jun 12 export-control directive that forced Anthropic to disable Fable 5 and Mythos 5 globally turns regulatory access into an architecture variable. A model that is best-in-class on Monday can be unavailable by Friday for reasons outside the vendor's control. Enterprise architecture should now treat top-tier closed models as revocable dependencies and design fallback routing and capability-degradation plans accordingly. Source: VentureBeat; MarkTechPost. ### Text diffusion enters open weights _Examples:_ DiffusionGemma, Gemma 4 backbone. DiffusionGemma brings block-diffusion text generation into the open-weight mainstream with native vLLM support and ~1,000+ tok/s throughput. The pattern matters because it offers a different latency/throughput profile than autoregressive decoding for interactive and local workloads. Architects evaluating local inference should add a diffusion option to their benchmark set rather than assuming autoregressive is the only path. Source: Google blog; Hugging Face. ### Frontier shipping concentrated in one vendor _Examples:_ Anthropic Fable 5, Gemini 3.5 Pro pending, GPT-5.6 rumor only. For the second straight issue, the only new frontier model came from Anthropic, while Google's Pro slipped and OpenAI's next model stayed a rumor. That concentration means the frontier's cadence — and now its availability — depends heavily on a single lab. Buyers should diversify model routing across vendors and keep a credible open/local tier so a single vendor's release or takedown cannot stall production. Source: Anthropic launch; Artificial Analysis; TechTimes. ## Benchmark moves ### Artificial Analysis Intelligence Index Claude Fable 5 debuted #1 at 64.9, roughly five points ahead of GPT-5.5, and set the highest score on five of the ten underlying benchmarks - Claude Fable 5: 64.9 - GPT-5.5: ~60 - Gemini 3.1 Pro: ~57 Source: [Artificial Analysis](https://artificialanalysis.ai/articles/claude-fable-5-mythos-intelligence-index). ### SWE-Bench Pro (coding) Fable 5's vendor-scaffold 80.3% widens the headline closed lead, but it is unreplicated by Scale SEAL/Epoch; independent vals.ai shows 95% on SWE-Bench Verified - Claude Fable 5 (vendor scaffold): 80.3% - Claude Opus 4.8: 69.2% - GPT-5.5: 58.6% Source: [morphllm / vals.ai; vendor harness (contested)](https://www.morphllm.com/swe-bench-pro). ### Open-weight intelligence MiniMax-M3 (55, weights pending) would lead open weights once released; North Mini Code lands at 27.6 in the efficient tier - MiniMax-M3 (pending): 55 - North Mini Code: 27.6 Source: [Artificial Analysis](https://artificialanalysis.ai/articles/claude-fable-5-mythos). ## Tier scorecard _As of 2026-06-13._ | Tier | Leader | Challenger | Note | |---|---|---|---| | Closed frontier | Claude Opus 4.8 | Claude Fable 5 (suspended) | Fable 5 debuted #1 (AA 64.9) but was force-disabled Jun 12; Opus 4.8 is the working default again until access is restored. | | Open frontier | DeepSeek V4-Pro | MiniMax-M3 (weights pending) | No open frontier text model displaced the April leaders in-window; MiniMax-M3's 55 AA Index would contend once weights ship. | | Reasoning | Claude Opus 4.8 | GPT-5.5 | Fable 5 set the reasoning bar before its takedown; with it suspended, Opus 4.8 leads the available closed reasoning tier. | | Coding | Claude Opus 4.8 | GPT-5.5 | Fable 5's 80.3% SWE-Bench Pro is a contested vendor figure and the model is suspended; Opus 4.8 remains the dependable coding default. | | Multimodal | Gemini 3.1 Pro | DiffusionGemma | Gemini remains the general multimodal reference; DiffusionGemma opens a low-latency open diffusion branch. | | Edge / small | Mellum2 | North Mini Code | Efficient open coding/sub-agent models keep widening; North Mini Code joins Mellum2 as a cheap self-host routing node. | ## Vendor signals - **2026-06-12 · Anthropic — A U.S. export-control directive forced Anthropic to disable Fable 5 and Mythos 5 for all customers; queries fall back to Opus 4.8** - Top-tier model availability is now a sovereign/regulatory variable, not just an uptime SLA. Buyers should require contractual clarity on access continuity and design fallback routing before standardizing on any single closed flagship. - _Source:_ [VentureBeat; MarkTechPost](https://venturebeat.com/technology/anthropic-blocks-all-public-access-to-claude-fable-5-mythos-5-following-us-government-order-what-enterprises-should-do) - **2026-06-09 · Anthropic — Fable 5 priced at $10/$50 per MTok (~2x Opus 4.8); included on paid tiers only through Jun 22, then reverting to usage credits** - The top-tier price ceiling moved up and the free-access window is short. Operators should model the post-Jun 22 cost cliff and route only high-value work to Fable 5, keeping cheaper models for routine calls. - _Source:_ [Anthropic launch](https://www.anthropic.com/news/claude-fable-5-mythos-5) - **2026-06-11 · xAI — Launched the Grok Build Plugin Marketplace bundling skills, MCP servers, and agents (commit-SHA-pinned), with partners MongoDB, Vercel, Sentry, Chrome DevTools, and Cloudflare** - xAI is competing on agent tooling and distribution rather than a new frontier model this window. Platform teams should weigh marketplace lock-in and pinning guarantees when evaluating agent ecosystems. - _Source:_ [x.ai](https://x.ai/news/grok-plugin-marketplace) - **2026-06-11 · OpenAI — Acquired Ona (Gitpod) for cloud sandboxes that keep long-running agents alive, folding it into Codex (5M+ weekly users)** - Durable long-running-agent infrastructure is being absorbed into the model layer, narrowing 'agent persistence' as a standalone wedge. Architects building long-horizon agents should expect this capability to become a platform feature rather than a separate purchase. - _Source:_ [SiliconANGLE](https://siliconangle.com/2026/06/11/openai-acquires-ai-agent-orchestration-startup-ona/) ## Watchlist - **Jun 14-30 — Fable 5 / Mythos 5 access restoration.** Whether Anthropic restores a top-tier model — and with what geo-gating or KYC controls — sets the precedent for sovereign access risk and determines whether Fable 5 re-enters the closed-frontier scorecard. - **Jun 14-30 — Gemini 3.5 Pro GA and first independent benchmark.** Google's Pro has slipped to the edge of its June commitment. A GA with an independent Artificial Analysis pass will show whether it lands above or below Fable 5 and GPT-5.5. - **Jun-Jul — MiniMax-M3 weights release.** If MiniMax ships the weights at its announced 55 AA Index, it becomes the leading open-weights model and a credible self-host alternative to closed frontiers. - **Jun-Aug — Independent SWE-Bench Pro replication of Fable 5.** Fable 5's 80.3% is a vendor-harness figure. An Epoch or Scale SEAL replication will confirm or deflate the coding-lead claim that buyers are being asked to act on. ## Changelog - Added Claude Fable 5, DiffusionGemma, and North Mini Code to the LLM tree; reframed W24 around a frontier launch-and-takedown and an open text-diffusion efficiency path. --- Source of truth: `src/data/industry/models/2026-W24.ts`. Canonical HTML: . PDF: . Tree: .