2023 – 2026
Llama Versions
Meta's current frontier-AI model is Muse Wonder, released October 12, 2026 under Meta Superintelligence Labs — closed-weights, built for long-horizon agentic and coding work, with a 1M-token context window, callable through the Meta Model API and the Muse Code terminal agent. Meta's own docs still label it a preview, and it comes in two tiers: the API model, muse-wonder-1.0, at $4 / $20 per million input / output tokens — roughly three times Muse Spark's price, with no cheaper contributor tier — and Muse Wonder Full, a higher-capability variant Meta sells only inside Muse Code's two top subscription plans and does not serve on the API at all. Three days later, on October 15, 2026, Meta did the thing it had promised since August: it released Muse Spark Open, an 816-billion-parameter mixture-of-experts model (42B active) that shares Muse Spark 1.3's base, as downloadable weights on HuggingFace — under a new Muse Model License rather than Apache 2.0 or a Llama Community License, with a $20 million-revenue clause for anyone selling it as hosted inference and a required “Built with Muse Spark Open” credit, but no >700M-MAU carve-out and no EU exclusion. It is Meta's first frontier-scale open-weights release since Llama 3.1 405B in July 2024, and it sits one generation behind the closed flagship, which is a shape the Llama era never had. Muse Spark 1.3 (September 2, 2026) stays on the API as the cost tier below Wonder, with its “max reasoning” mode live since September 4 on the standard tier only. On September 8, 2026 Meta wrapped Muse Spark 1.3 in a consumer product carrying the family's own name: Muse, a personal AI agent that lives on a per-user cloud computer with its own browser and acts across email, calendar, and checkout, free with $20 and $100 monthly tiers above it. It is a product rather than a model — no weights, no model id of its own — so it has no row below; Meta says Muse Wonder will power it next, subscribers first. At Meta Connect on September 23, 2026 the lab gave that agent a voice and a face: Muse Realtime Voice, a real-time conversational speech model, and Muse Realtime Avatar, an embodiment model that turns its speech-token stream into synchronized video at roughly 870 ms of latency. Both ship inside the Muse product rather than on the Meta Model API — no model id, no endpoint, no published weights — so neither carries a row below either. The day before the flagship, on September 1, 2026, the same lab shipped Muse Voice Transcribe, its first real-time audio-perception model — streaming speech recognition, speaker diarization and endpointing in one model, also closed-weights, billed per minute of audio. On August 10, 2026 it released Muse Glimmer 30B, a local agent model with open weights under Apache 2.0 — Meta's first downloadable frontier-lab model since Llama 4, and the first ever to ship without the Llama license's >700M-MAU and EU carve-outs. The Muse line had been closed-weights since its April 2026 launch, Meta's first frontier surface shipped that way since Llama 2 in July 2023; Glimmer partly reopened it, one size class below the flagship; Muse Spark Open, promised three times over August and September and shipped on October 15, reopened it at frontier scale — while the newest model, Muse Wonder, stays closed. The same lab shipped Muse Image, its first in-house image-generation model, on July 7, 2026, and previewed Muse Video alongside it; Muse Image reached the Meta Model API for outside developers on August 26, 2026 at $0.01 per image, still closed-weights. The open-weights Llama line itself runs from LLaMA 1 (February 2023, leaked the next month) through Llama 4 Maverick and Llama 4 Scout (April 2025). I track every Meta release here — with HuggingFace ids, parameter counts, context windows, and license terms — because the licensing and infrastructure terms change too often for marketing pages to keep up. Below the table: the March 2023 LLaMA leak, the FAIR vs. GenAI org split, the Llama 4 Behemoth delay, the June 2025 Scale AI acqui-hire and Meta Superintelligence Labs reorg, and the closed-weights turn.
The March 2023 LLaMA leak
Meta released LLaMA 1 on February 24, 2023 as a research-only model gated by application form, accessible to academic and government applicants and not under any open-source license. On March 3, 2023 — nine days later — a user posted a torrent containing the 7B and 65B weights to 4chan's /g/ technology board under the handle llamanon. The same day, a pull request was filed against Meta's official Llama GitHub repository proposing to add the magnet link to the README. The torrent reportedly pulled directly from Facebook's CDN at high speed, embedded with a unique download URL traceable to the leaker's gated-access grant.
Meta filed DMCA takedowns through HuggingFace and GitHub through March 20, 2023, but the weights had already propagated. Coverage at the time in The Register and DeepLearning.AI's The Batch documents the propagation timeline. Within weeks, the leaked LLaMA 1 weights were the de facto foundation for an enormous open-source fine-tune ecosystem — Alpaca, Vicuna, Guanaco, and dozens of others — on HuggingFace.
The leak is widely credited with forcing Meta's hand on Llama 2: with the weights already in the wild, the marginal cost of an official open-weights commercial release dropped to near zero, while the upside (developer mindshare, ecosystem effects, reduced lawsuit risk) was substantial. Llama 2 shipped with permissive commercial terms four months later. The decision-tree shape of the leak → commercial open release pattern is the load-bearing precondition for everything that followed in the Llama story through 2025.
The Llama Community License and the >700M-MAU carve-out
Llama 2 introduced the bespoke Llama 2 Community License Agreement — not an OSI-approved open-source license, but a Meta-authored license with permissive commercial terms and a single load-bearing carve-out: companies whose products had more than 700 million monthly active users on the Llama 2 release date (July 18, 2023) must request a separate license from Meta. The carve-out is a deliberate exclusion aimed at TikTok, Google, Apple, and other direct platform competitors; reading the precise language requires the actual PDF, which Meta hosts at llama.com/license and ai.meta.com/llama/license.
The carve-out has been preserved through every subsequent Llama license: Llama 3 Community License (April 2024) added an attribution requirement that derivative model names include the “Llama 3” prefix; the Llama 3.1 / 3.2 / 3.3 licenses extended the naming convention to require the “Llama” prefix on derivatives; the Llama 4 Community License preserved the same general shape. The Open Source Initiative has consistently said the Llama license does not meet the Open Source Definition because the use-restriction (any restriction tied to who you are, not what you do) is incompatible with the OSD — this is the substantive basis for the “source-available, not open source” framing of the line.
Llama 3.2 added a regional carve-out: the multimodal models (11B and 90B Vision) were excluded from EU-domiciled individuals and EU-headquartered companies, citing regulatory uncertainty under the EU AI Act, GDPR, and Digital Markets Act. The text-only 1B / 3B models remained available in the EU. Llama 4 carries the same EU exclusion, in identical wording — and because every Llama 4 model (Maverick, Scout, Behemoth) is natively multimodal, the restriction effectively covers the entire Llama 4 line for EU-domiciled individuals and EU-headquartered companies. EU-based end-users may still use Llama-4-powered services originating outside the EU: the restriction “does not apply to end users of a product or service that incorporates any such multimodal models.” A separate EU instrument arrived on July 28, 2026, when Meta said it would sign the EU AI Act Code of Practice on Transparency of AI-Generated Content — that one governs labeling and provenance of generated media (Content Seal is Meta's own implementation), not who may download and deploy the weights, so it leaves the license carve-outs untouched.
A sourcing detail worth knowing if you go looking for that language: the EU exclusion is not in the Community License text itself. It lives in the matching Acceptable Use Policy, which each license incorporates by reference, and it operates by withholding the Section 1(a) grant. The license PDF is silent on the EU; searching it alone will tell you the restriction doesn't exist. Re-verified 2026-10-19 against the Llama 4 Acceptable Use Policy and Community License as published in Meta's llama-models repo, alongside the Llama 3.2 equivalents — the Llama 4 wording is still identical to Llama 3.2's, end-user exemption included. The same pass confirmed the >700M-MAU carve-out intact in Llama 4, pegged to the Llama 4 version release date (April 5, 2025) and measured over the preceding calendar month.
The bespoke-license era has an end date, or at least an exception. Muse Glimmer, released August 10, 2026, ships under Apache 2.0 — a standard, OSI-approved license, and the first Meta frontier-lab model in the line's history not governed by a Meta-authored one. Practically, the two restrictions that have shaped every “can I ship with this?” question since July 2023 are simply absent: no >700M-MAU carve-out, so the platform competitors the Llama license was drawn to exclude are not excluded, and no EU carve-out, even though the model takes image input and would have tripped the multimodal restriction under a Llama license. The naming convention is gone too — derivatives need no “Llama” prefix. It is also published outside the Llama plumbing: the weights sit in a new meta-models HuggingFace org rather than meta-llama, and there is no Muse generation directory in the llama-models repo that hosts the per-generation license and use-policy texts. Whether Apache 2.0 would become the shape of future open Muse releases was the open question through September — Meta had announced on August 10, 2026 that an open-weights Muse Spark was coming, restated it on August 20 and September 2, and never named a license.
The answer, on October 15, 2026, was a third shape. Muse Spark Open ships under the Muse Model License — a Meta-authored license again, but not the Llama one. It grants use, modification, fine-tuning, distillation, distribution and sale, and attaches three conditions: the license and its Usage Policy travel with every copy; products must prominently display “Built with Muse Spark Open”; and anyone offering the model as a hosted service whose aggregate gross revenue with affiliates exceeds $20 million in any twelve-month period must notify Meta and sign a separate agreement. Set against the Llama Community License, the carve-out moved from who you are (700 million monthly users on a release date) to what you sell (inference as a service, above a revenue line), and the attribution requirement moved from the derivative's name to the product's interface. There is no EU exclusion — the only European text is the usual entity designation — and no “Llama” naming rule. The download is gated on both HuggingFace and Meta's own site. So the line now carries three license shapes at once: Apache 2.0 on the local-tier Glimmer, the Muse Model License on the frontier-scale Spark Open, and nothing at all on the API models, which as of October 19, 2026 remain proprietary and closed-weights — Muse Wonder (closed, with its Full variant sold only inside Muse Code), the three hosted Muse Spark versions, Muse Image, and Muse Voice Transcribe. The consumer Muse agent that launched on September 8 changes nothing here either — it is a product built on the closed models, with no weights of its own to license — and neither do Muse Realtime Voice and Muse Realtime Avatar, introduced inside that agent on September 23, which Meta has not put on the Model API, published weights for, or attached a license to at all.
FAIR, GenAI, and the org evolution
Meta's AI research home through 2022 was FAIR (Fundamental AI Research), founded in 2013 under Yann LeCun as Chief AI Scientist and led from 2023 by Joelle Pineau. FAIR's mandate was long-horizon basic research; its publication culture was open and academically-styled. LLaMA 1 was a FAIR project.
After ChatGPT's November 2022 launch caught Meta flat-footed, the company formed a separate Generative AI organization (GenAI) in February 2023, led by VP Ahmad Al-Dahle (who departed Meta in January 2026 to become CTO of Airbnb) and tasked with shipping product-grade generative AI on a faster cadence than FAIR's research timeline. Llama 2 and onward shifted progressively into GenAI under Manohar Paluri; FAIR was pushed toward longer-horizon work as the shipping pace of the GenAI org accelerated through 2024.
Through late 2024 and into 2025, FAIR's relevance to Meta's shipping AI products visibly waned. Internal reporting in April 2025 described FAIR as “dying a slow death.” Joelle Pineau announced her departure on April 1, 2025, last day May 30, 2025, after eight years leading FAIR; she was the most prominent internal advocate for open-source releases. Her exit set up the structural reorganization that came two months later.
The Scale AI acqui-hire and Meta Superintelligence Labs (June 2025)
On June 12–13, 2025, Meta announced a $14.3 billion investment for a 49% non-voting stake in Scale AI, valuing Scale at over $29 billion. The deal was structurally an acqui-hire: its purpose was to bring Scale CEO Alexandr Wang (then 28) to Meta as Chief AI Officer. Wang stepped down as Scale CEO but remained on Scale's board. Coverage in CNBC and Fortune.
On June 30, 2025, Mark Zuckerberg announced the formation of Meta Superintelligence Labs (MSL) with Wang as Chief AI Officer leading the new unit and former GitHub CEO Nat Friedman leading AI products. FAIR and GenAI were both consolidated under MSL; a new TBD Lab sub-group was created to work on next-generation LLMs. CNBC published the internal memo. The reorganization was the structural endpoint of Pineau's departure two months earlier and of the Llama 4 Behemoth delay reporting through May 2025.
Friction between Meta and Scale AI emerged through August 2025 as Scale's enterprise-data-labeling business saw revenue impact (competitors stopped sending training data to a Meta-owned vendor); TechCrunch covered the cracks in the partnership. MSL itself restructured into four sub-groups in August 2025.
Yann LeCun departs (November 2025) — AMI Labs
On November 19, 2025, Chief AI Scientist Yann LeCun announced his departure from Meta to launch his own startup focused on Advanced Machine Intelligence and “world models.” Reporting in CNBC and Bloomberg tied the decision to LeCun being asked to report to Wang — a structural demotion, since Wang's closed-source product orientation conflicts with LeCun's long-held public position that scaling LLMs is not a path to AGI and that open research is foundational to the field.
LeCun named the startup AMI Labs (Advanced Machine Intelligence) on December 18, 2025 and launched the public-facing site at amilabs.xyz in January 2026. On March 9, 2026 AMI announced a $1.03 billion seed round at a $3.5 billion pre-money valuation, co-led by Cathay Innovation, Greycroft, Hiro Capital, HV Capital, and Bezos Expeditions. The stated mission is “intelligent systems that understand the real world” rather than language-only LLMs. Meta is not an investor but a partnership is reportedly under discussion (LeCun has publicly suggested Meta could be AMI's first client), and AMI has a clinical-AI partnership with Nabla. With both Pineau and LeCun out, the open-research mandate inside Meta effectively ended at MSL's June 2025 formation.
The closed-weights turn — Muse Spark (April 2026)
On April 8, 2026, Meta Superintelligence Labs released Muse Spark, its first model since the June 2025 reorganization. Muse Spark shipped closed-weights, API-only, in private preview — the first frontier-AI model from Meta released without open weights since Llama 2 in July 2023. Branded under the new Muse family rather than Llama. The announcement is at ai.meta.com/blog/introducing-muse-spark-msl; coverage in CNBC and VentureBeat. Meta has stated it “hopes to open-source future versions” of Muse, but the launch model is proprietary.
Muse Spark is natively multimodal and ships with three operating modes — Instant (fast responses, no extended reasoning), Thinking (chain-of-thought), and Contemplating, which orchestrates parallel sub-agents (“thinking wider, not longer”), positioned competitively against Gemini Deep Think and the OpenAI o-series. Several outlets characterized the launch as the end of Meta's open-weights frontier-AI era. The closed-weights turn is the dramatic reversal of Mark Zuckerberg's July 2024 “Open Source AI Is the Path Forward” letter, which had argued (twenty-one months earlier) that open-source AI's trajectory would mirror Linux's path from inferior-but-cheap to dominant-via-ecosystem.
The line has since moved twice in one week without reversing course on weights. On July 7, 2026 MSL shipped Muse Image and previewed Muse Video (announcement), both closed-weights. On July 9, 2026 it shipped Muse Spark 1.1 (announcement) and launched a public preview of the Meta Model API. That API is the one partial opening so far: the original Muse Spark was private-preview only, and Muse Spark 1.1 is the first Meta frontier model any outside developer can call. It arrived three days after Meta switched off the equivalent service for its open models: the public preview of the Llama API, the first-party hosted endpoint for Llama 4 that Meta announced at LlamaCon in April 2025, was retired on July 6, 2026 (per Promptfoo's provider docs, which link Meta's deprecation notice; Meta has since taken that notice down). Access, not weights — there was still no HuggingFace release, and Meta's “hopes to open-source future versions” framing from April had not yet been acted on. The pattern repeated on July 24, 2026, when Meta wired the model's planning and tool use into Meta AI itself as consumer features — scheduled tasks, calendar and email connections, research syntheses, generated slides (newsroom post). Wider reach, same posture on weights.
On August 5, 2026 the line moved again, in a direction that says something about what Meta is selling. MSL shipped Muse Spark 1.2 — a coding-focused update — together with Muse Code, a terminal coding agent the model was co-trained with, shipped in beta (announcement). Weights stayed closed, but the commercial terms opened a new seam: alongside the standard API tier, Meta introduced a muse-spark-1.2-contributor tier at roughly a twelfth the input price and a twenty-first the output price, in exchange for permission to train future Meta models on the customer's prompts and completions. Where the Llama era traded weights for ecosystem, the Muse era is trading price for training data. The announcement also moved hosts: it was published on research.meta.ai, which now carries the Muse-line posts, and llama.com now redirects to developer.meta.com/ai/.
Five days later the turn partly reversed. On August 10, 2026 MSL released Muse Glimmer, a 30-billion-parameter local agent model, with open weights under Apache 2.0 (announcement) — the first downloadable model from Meta's frontier lab since Llama 4 in April 2025, and the first ever under a standard open-source license rather than a bespoke Llama Community License. Meta framed it as “keeping with our long tradition of sharing fundamental AI research.” The reopening is real but bounded: Glimmer is distilled from Muse Spark and sits a size class below it, and the flagship Muse Spark models stayed closed and API-only. What it does settle is the April 2026 “hopes to open-source future versions” framing — that has now been acted on once, at the small end of the line.
The same announcement went further than the model it shipped. On August 10, 2026, Chief AI Officer Alexandr Wang said Meta would also release open weights for a version of Muse Spark 1.2 — the flagship — “soon,” with no date attached. Meta restated the plan in its own words on August 20, 2026, opening a research post on the model's multimodal evaluations with the line that it was publishing them “ahead of the open-weights release” (announcement). That would move the reopening from the local tier to frontier scale, which is the question Glimmer left open. Through September it had not happened — the meta-models org held only the four Muse Glimmer repos, and Meta named neither a date nor a license. It happened on October 15, 2026, sixty-six days after the first promise, and is covered below.
The same day, Mark Zuckerberg published “The Future is for Everyone”, a letter proposing a philosophy of “individual empowerment as the source of prosperity, invention as the primary purpose of superintelligence, and balance of power as the foundation of safety,” and asking whether superintelligence “will be centralized and restricted to a few institutions, or will it be a tool that empowers everyone.” It is the closest thing to a successor to the July 2024 open-source letter, and it landed alongside the first open-weights release since the turn — but it argues from access and distribution rather than from open weights, and it does not mention Llama, Muse, or open weights anywhere in its text.
What actually moved next was access again. On August 26, 2026, sixteen days after the open-weights promise and seven weeks after the model itself launched, Meta put Muse Image on the Meta Model API as muse-image-1.0 at $0.01 per image, resolving the “still evaluating whether it will make Muse Image available to outside developers” line from July. The weights stayed closed. That is now the line's settled rhythm at the frontier: each surface opens to developers as a metered endpoint, months after it opens to consumers, and never as a download. Worth noting where the announcement landed — a post on the AI developer blog, with nothing on research.meta.ai, ai.meta.com, or the newsroom. Meta now ships platform news and research news to different addresses.
Then, on August 31, 2026, the packaging changed rather than the model. Meta took Muse Code out of beta — four weeks after shipping it — and put flat-rate monthly subscriptions behind it, in three tiers (Everyday, High, and Power Usage) sold through Meta's Accounts Center and metered in requests per five hours instead of tokens (developer blog, subscription docs). The same release added staged multi-agent workflows, messaging between live sessions, and a conversation rewind. That gives the same closed model three distinct commercial shapes in under a month: metered tokens at the standard rate, tokens at roughly a twelfth the price if Meta may train on them, and a flat monthly fee for the agent that drives them. Through the end of August the shape of the arc was hard to miss: every change Meta had shipped at the frontier since the April 2026 launch was about how you buy access, and the one announced change to who may hold the weights, promised on August 10, had not landed. Where the announcement went said the same thing: the developer blog again, with nothing on research.meta.ai or the newsroom.
Then the models resumed. On September 1, 2026 MSL shipped Muse Voice Transcribe, its first real-time audio-perception model (announcement) — a new modality for the line, and its first product priced per minute of audio rather than per token. A day later, on September 2, 2026, it shipped Muse Spark 1.3 (announcement), an agentic-workflow update to the flagship. Both are closed-weights, so the posture is unchanged — but two things about the 1.3 launch are worth recording. It shipped incomplete, and was completed quietly two days later: Meta held its top “max reasoning” mode back “shortly after we finish additional safety testing,” so for two days the flagship was generally available while its highest setting was not — and, as VentureBeat pointed out on September 3, several of the launch's strongest disclosed scores belonged to that unshipped configuration rather than to the xhigh setting developers could actually call. On September 4, 2026 max went live on the Meta Model API and in Muse Code, on the standard tier only. Meta marked the change by editing the September 2 post in place rather than publishing a new one, and left both the post's published and its modified date reading September 2 — so the release is invisible to anyone diffing headlines, dates, or the blog index, and only the reasoning docs and the post body carry it. Nothing was concealed about the numbers; what was hard to see was the moment the gap closed. And it shipped narrower on one axis: Meta's own docs flag audio understanding on 1.3 as not fully supported and send audio work back to Muse Spark 1.2 or to the new transcription model. The open-weights promise was restated a third time in the same post — “bigger models, the Muse Spark open weights release, and more” — and this time without naming a version, so it is no longer clear that what was promised on August 10 for Muse Spark 1.2 is still what is coming. Zuckerberg restated it himself on X the same day, also without a version and in the plural — open-weights Muse Spark “releases” — which moved the promise up to the CEO without moving it any closer to a date (The Register). The one time frame anyone attached to it — “in the coming weeks,” per VentureBeat's account of the August 10 statement — came and went. Through the end of September, five months in, the Muse line had published open weights exactly once, at the size class furthest from the frontier.
Six days after that, the brand landed on a product. On September 8, 2026 Meta launched Muse — a consumer personal AI agent, carrying the family name itself, running on Muse Spark 1.3 (newsroom). Each user gets a dedicated Linux VM with a real browser; a separate host-side agent called Sentinel, which the model cannot override, approves every connector action and every network request, and the model is never shown a real credential (engineering writeup). It is free for most use with $20 and $100 monthly tiers above it, it carries no advertising, and Meta says a confidential-VM mode it cannot itself read is coming before the end of the year. For this page the disposition is the same as Muse Code's: a harness with no weights and no model id gets no row. But it is the clearest statement yet of what the closed-weights turn bought. Every Llama release was, in the end, a download. Everything the Muse line has shipped since April 2026 is a service you reach across Meta's network — a metered API, a data-for-discount tier, a subscription CLI, now a consumer agent running on a Meta-operated VM — and the one thing Meta has promised at the frontier and not delivered is still the thing the Llama era handed over by default. The name is now doing triple duty — a model family, a coding CLI, and a consumer app — which is worth keeping straight: on this page “Muse” alone means the agent, and the models carry their full names.
The following week the packaging moved twice more. On September 15, 2026 Meta launched Meta One, a consumer subscription spanning Instagram, Facebook, WhatsApp and Meta AI, whose Core ($7.99 a month) and Premium ($19.99 a month) bundles are sold partly on headroom for “creating and editing images and generating videos powered by Muse models” (newsroom) — the line reaching consumers as a metered allowance inside apps they already had, and a fifth distinct way to pay for models nobody can download. Three days later, on September 18, 2026, Meta opened the consumer agent's connector layer to outside developers at muse.ai/platform, and put SAM 3.1 on the Meta Model API as sam-3.1, at $2.50 per 1,000 images and $0.20 per 1,000 video frames (docs). SAM is a FAIR-line segmentation model rather than a Muse one, so it earns no row here — but it is the first non-Muse family that API has sold, and it runs the pattern backwards: Meta's own docs describe the SAM family as open-weight research models, and the SAM 3.1 checkpoint has been downloadable since March 27, 2026 (announcement), so here the metered endpoint arrives on top of the weights instead of in place of them.
Then the whole quarter's argument arrived on a stage. At Meta Connect on September 23, 2026, Meta Superintelligence Labs introduced two new models — Muse Realtime Voice, a real-time conversational speech model, and Muse Realtime Avatar, which consumes the same speech-token stream and generates synchronized video at roughly 870 ms from end-of-turn to first byte (research post, Connect recap). They are genuine frontier-lab models with a published architecture and published evaluations against Runway and HeyGen — and they are the first Muse models that arrived with no way to call them at all. Muse Spark went closed-weights but got an API; Muse Image and Muse Voice Transcribe followed it onto that API; Muse Glimmer went the other way and became a download. These two are neither: Meta's own Model API roster still lists five families and names neither of them, there is no model id, no endpoint, no price, and no HuggingFace release. The only way to reach them is to talk to the consumer app. The same keynote pushed that app onto more surfaces rather than fewer — a Mac build with computer use, AI glasses “in the coming months,” an email address of its own, a pocket voice device called Muse Charm with “more to share later this year,” and a much longer connector roster including Walmart, Best Buy, Instacart, Expedia, GitHub and Notion. Meanwhile the one thing promised at the frontier and not delivered went unmentioned: Connect restated the open-weights Muse Spark release nowhere, and the meta-models org still held only the four Muse Glimmer repos the next morning.
The week after Connect the selling moved up a level, from products to an organization. On September 28, 2026 Zuckerberg announced Meta Enterprise Platform, which he called “the next major pillar of our business,” to take Meta's AI stack — the Muse agent, Meta Business Agent, what his post calls the Muse API, and Muse Code — to businesses and developers, and hired former MongoDB CEO Chirantan “CJ” Desai to run it as Chief Enterprise Platform Officer, reporting directly to him (newsroom). The next day Meta launched Muse for Small Business, a set of business skills and connectors inside the consumer agent, which by then was available in Canada as well as the US (newsroom). Neither announcement mentioned weights. Every item the enterprise post names is something you reach across Meta's network; neither Muse Glimmer nor Llama is named.
October opened with the rulebook rather than a model. On October 2, 2026 Meta published an update to what it now calls the Meta Superintelligence Scaling Framework, the policy it says governs how its most capable models are trained, evaluated and released (research post). The update extends its loss-of-control requirements to containment during training and evaluation, expands the risk considerations it applies to open-weight releases specifically, and announces a new AI committee of Meta's board to review future changes; Meta tied it to commitments made at the White House that week. Two releases followed inside two weeks, and each cites the framework.
On October 12, 2026 MSL shipped Muse Wonder and Muse Wonder Full, “our most capable models to date, built on the groundwork we laid with Muse Spark” (newsroom, research post) — the first model to move the frontier above Muse Spark since April. Closed-weights, and sold in a shape the line had not used before: Muse Wonder on the Meta Model API at $4 / $20 per million tokens with no contributor tier, and Muse Wonder Full — the better of the two — nowhere on the API at all, available only through Muse Code's two top subscription plans. Where the Llama era's best model was a download and the early Muse era's best model was a metered endpoint, the best model Meta now sells is bundled with its coding agent. Meta's docs still call Muse Wonder a preview.
Three days later, on October 15, 2026, the promise from August landed. MSL released Muse Spark Open — 816 billion parameters, 42 billion active, the same base as Muse Spark 1.3 — as downloadable weights on HuggingFace (announcement), calling it “the most capable US open-weight model to date.” It is Meta's first frontier-scale open-weights release since Llama 3.1 405B in July 2024, and the first since the closed-weights turn. The license is neither Apache 2.0 nor a Llama Community License but a new Muse Model License — “limited commercial terms, which allow many developers to use the model for free,” in Meta's words, with a $20 million-revenue clause for hosted-inference sellers and a required “Built with Muse Spark Open” credit (details in the license section above). Three things about the timing are worth recording. The promise was made for Muse Spark 1.2, restated without a version, and fulfilled with 1.3's base — the version moved on while the words stayed the same. The repos existed on HuggingFace from September 15 as private, gated repositories, so a month of “nothing published” was true of what the public could see and not of what Meta had staged. And the weights arrived three days after Muse Wonder superseded the model they reproduce, which gives the Muse line a posture the Llama line never had: the newest model closed and partly subscription-only, the previous generation open under a Meta-authored license with conditions, and the local tier open under Apache 2.0. The open weights trail the closed frontier by one generation.
The Muse line is treated on this page as Llama's successor — same Meta organization (MSL), same flagship-frontier slot — even though it is not Llama-branded. The open-versus-closed question that defined the Muse line's first six months now has a settled shape rather than an open one: Muse Glimmer answered it for the local tier in August, and Muse Spark Open answered it at frontier scale in October, each under a different license, while the newest model stayed closed. Whether that one-generation lag holds — whether a Muse Wonder Open follows, and under which terms — is the question going forward. No new Llama has shipped since April 2025 and none is announced; the reopening arrived under the Muse brand and two different licenses instead.
Where to run Llama
Llama is the most widely-distributed frontier-AI line because the weights are open. Inference paths through 2025–2026 break into three categories.
Self-host. Download from the HuggingFace meta-llama org and run with vLLM, llama.cpp, Ollama, MLX (Apple Silicon), or TensorRT-LLM. The 1B / 3B Llama 3.2 edge models are specifically designed for on-device deployment. Since August 10, 2026 the self-host path also covers a Muse model: Muse Glimmer 30B ships open weights under Apache 2.0 from the separate meta-models org, quantized to fit a single 24 GB or 32 GB consumer GPU, with LM Studio, Unsloth, ExecuTorch and SGLang added to the runtime list. Since October 15, 2026 it also covers a frontier-scale one: Muse Spark Open, 816B parameters under the Muse Model License, from the same meta-models org (gated download) — about 537 GB of weights in NVFP4 or 1.65 TB in BF16, so “self-host” here means a four- or eight-GPU Blackwell node or a pair of M5 Ultra Mac Studios under MLX, not a desktop GPU.
Hosted-inference providers. Together AI, Fireworks AI, Groq (long notable for very high tokens-per-second on Llama 3 70B, but no longer a Llama host for most customers: its deprecation log shows Llama 4 Maverick shut down on March 9, 2026, Llama 4 Scout on July 17, and Llama 3.1 8B and Llama 3.3 70B on August 16, all in favor of OpenAI's and Alibaba's open models, with only committed-spend enterprise contracts exempt — though it is back for the open Muse, as a named launch partner for Muse Spark Open), Replicate, Perplexity Labs, Cerebras, SambaNova. Not every one of them still carries the newest weights: for Llama 4 Maverick, Artificial Analysis tracks six API hosts as of October 19, 2026 — Amazon Bedrock, Azure, DeepInfra, DigitalOcean, Novita and Parasail; Together AI has dropped off that list since late September. For Muse Spark Open the launch-partner hosts are Together AI, Fireworks AI, Baseten, Groq, Modal, Nebius and OpenRouter, plus the Amazon SageMaker, Google Cloud Model Garden and Microsoft Foundry catalogs. Pricing is typically a fraction of comparable closed-weights frontier-model API rates because providers compete on inference cost, not model rights.
Hyperscalers. AWS Bedrock, Azure AI (Microsoft was Meta's launch partner for Llama 2 in July 2023), Google Cloud Vertex AI, Oracle OCI, IBM watsonx. Meta's own Llama API (announced at LlamaCon 2025-04-29) was the first-party hosted option for the open-weights line until Meta retired its public preview on July 6, 2026 (per Promptfoo's provider docs, which link Meta's since-deleted deprecation notice); its developer portal now forwards to the Meta Model API docs, whose model roster lists no Llama model as of October 19, 2026. For hosted Llama, the third-party hosts named in this section are what remain. The Muse line now splits three ways. Its newest model is API-and-subscription only: the Meta Model API, which has served Muse models to outside developers since July 9, 2026, carries Muse Wonder (muse-wonder-1.0, since October 12, 2026, $4 / $20 per million tokens, standard tier only) above Muse Spark 1.3, 1.2 and 1.1, with the max reasoning setting live on Wonder and on 1.3's standard tier; Muse Wonder Full is reachable only through the Muse Code terminal agent on its Power or Maximum subscription plan. Muse Code is the first-party CLI on top of the API, out of beta since August 31, 2026, native on Windows as well as macOS and Linux since September 16, and billable either per token or on one of four flat monthly plans; OpenRouter is the first third-party route to the hosted models. The previous generation is a download: Muse Spark Open, since October 15, 2026, belongs to the self-host paragraph above and to the hosted-provider list, and is not on the Meta Model API at all. Muse Image joined the same API on August 26, 2026 as muse-image-1.0, at $0.01 per image, through /v1/images/generations and /v1/images/edits; OpenRouter routes it as meta/muse-image. Muse Voice Transcribe joined on September 1, 2026 as muse-voice-transcribe-1.0, on its own endpoints — a WebSocket at wss://api.meta.ai/v1/asr/realtime for live audio and POST /v1/asr/transcribe for recordings — billed at $0.18 per hour of audio rather than per token, and also wired into Meta AI for Mac and Muse Code for dictation. That API stopped being Muse-only on September 18, 2026, when Meta added SAM 3.1, its segmentation model, as sam-3.1 over POST /v1/responses — billed per image and per video frame rather than per token, and the one model on the API whose weights you can also just download. It is a FAIR-line model rather than a Muse one, so it has no row in the table above. Muse Glimmer, likewise, is not on that API — since August 10, 2026 it is a download, and belongs to the self-host paragraph above. Muse Image and the Muse Spark models are also live in the Meta AI app and on meta.ai, and since September 8, 2026 Muse Spark 1.3 also drives Muse, the consumer personal agent (Meta says Muse Wonder will power it next, subscribers first) — in the US and, since September 18, 2026, Canada, on iOS, Android, muse.ai, and inside WhatsApp, each user's agent running on its own Meta-hosted Linux VM, plus a Mac app since September 17, 2026 that can drive native applications with permission, and Meta's AI glasses promised “in the coming months” as of Connect on September 23. That is a way to use the model, not a way to run it: there is no endpoint, no model id, and no download behind it. The same is true twice over of Muse Realtime Voice and Muse Realtime Avatar, the conversational-speech and embodiment models Meta introduced on September 23 — they are not on the Meta Model API, not on HuggingFace, and not routed by anyone; the consumer app is the only place they exist. Note that llama.com now redirects to developer.meta.com/ai/, which as of October 19, 2026 forwards on again to dev.meta.ai, the Meta Model API portal — Meta's model pages and developer blog have moved to that host too — and the license and use-policy paths redirect with it.
People who shaped Llama
Mark Zuckerberg — CEO of Meta. The 2024 “Open Source AI Is the Path Forward” letter and the 2025 strategic decisions (Scale AI acqui-hire, MSL formation, Muse Spark launch) all run through Zuckerberg's office. The closed-weights turn reverses the public position the letter staked out twenty-one months earlier.
Yann LeCun — Chief AI Scientist 2013–2025, FAIR cofounder. 2018 Turing Award. Departed November 2025 to launch AMI Labs (Advanced Machine Intelligence), a world-models startup that emerged from stealth in January 2026 and closed a $1.03B seed at a $3.5B pre-money valuation on March 9, 2026.
Joelle Pineau — led FAIR 2023–2025. The internal advocate for open-source releases through the Llama 1–3 era. Departed May 2025 ahead of the MSL reorganization.
Ahmad Al-Dahle — VP of Generative AI at Meta through Llama 2 / 3 / 4; spokesman for the LMArena Maverick episode in April 2025. Departed Meta in January 2026 to become CTO of Airbnb (Airbnb announcement, January 14, 2026).
Alexandr Wang — Chief AI Officer of Meta since June 2025; head of Meta Superintelligence Labs. Previously CEO of Scale AI. The architect of the closed-weights pivot and the Muse line.
Nat Friedman — head of AI products at MSL since June 2025; previously CEO of GitHub.
Shengjia Zhao — Chief Scientist of Meta Superintelligence Labs since July 25, 2025, setting the lab's research agenda alongside Zuckerberg and Wang. Previously at OpenAI, where he was a co-creator of ChatGPT and GPT-4 (CNBC, TechCrunch). His appointment four months before LeCun's departure left MSL's scientific direction with a hire from a closed-weights lab rather than with FAIR's founding generation.
The competitive landscape
Llama is — through April 2025 — the dominant open-weights frontier-AI line by deployment volume. The closest open-weights competitors are Mistral (French; mixed Apache 2.0 / Mistral Research License / proprietary tiers across the line, with the December 2025 “Mistral 3” family relaunch returning the open releases to Apache 2.0 — see Mistral Versions), DeepSeek (Chinese, MIT-licensed for the V3 / R1 line and onward, the December 2024 / January 2025 inflection — see DeepSeek Versions), Alibaba's Qwen (also fully open-weights and dominant on HuggingFace leaderboards through 2025 — see Qwen Versions), and xAI's Grok 1 (open-weights only for the first generation, see Grok Versions). The closed-weights frontier competitors — ChatGPT, Claude, Gemini — have all stayed closed-weights since their inception. With Muse Spark in April 2026, Meta is the only major frontier lab to have started open-weights and pivoted closed — and, with Muse Glimmer in August 2026 and Muse Spark Open in October 2026, the only one to have pivoted partway back, releasing a local-tier model under Apache 2.0 and then a frontier-scale one under its own Muse Model License while keeping its newest model, Muse Wonder, closed. Meta's own framing for Muse Spark Open is “the most capable US open-weight model to date,” a claim scoped by nationality against the Chinese open-weights lines above; this page does not attempt a benchmark roundup or a ranking. The open question for the line going forward is whether the one-generation lag between Meta's closed frontier and its open weights holds, and under which license the next open release ships.