Muse Spark Open's weights are publicly available for download on Hugging Face, Amazon SageMaker AI, Google Cloud Model Garden and Microsoft Foundry Models under the Muse Model License, and the model is served by the API platforms Baseten, Fireworks AI, Groq, Modal, Nebius, OpenRouter and Together AI.
● OPEN · settles 2026-10-20
| Claim made in | Introducing Muse Spark Open, The Most Capable US Open-Weight Model to Date (research.meta.ai) |
| Bank record | Meta AI — see its full delivery record in the bank |
| Market opened | 2026-10-17 |
| Market type | Flash market (1–3 days) |
| Calls lock | 2026-10-19 08:00 Eastern Time (12:00 UTC) — 24 hours before the check, so nobody can call it with the answer already visible |
| Check time | 2026-10-20 08:00 Eastern Time (12:00 UTC) |
| Source of record | research.meta.ai |
Background
Meta has put the weights of its biggest Muse model on the table. Muse Spark Open is a natively multimodal mixture-of-experts model with 816 billion total parameters, 42 billion active per token, a 1.8-billion-parameter perception encoder and a context window of one million tokens, taking in text, images, video and audio. It is derived from the closed Muse Spark released in August, with extra safety post-training so it can stand on its own without a system harness around it. Meta bills it as the most capable US open-weight model to date, and its own scorecard, run at the highest reasoning setting, puts it at 89.2 on MCP-Atlas, 89.0 on GPQA Diamond and 76.4 on Terminal-Bench 2.1. The same table leaves it behind Kimi K3 and GLM 5.3 on several coding tests, and at 39 on the Artificial Analysis Intelligence Index. The release was also engineered to run on a desk: using Apple's MLX framework, two Mac Studios with M5 Ultra chips, each able to use up to 512GB of unified memory, can hold the entire model between them. The weights are downloadable from Hugging Face, Amazon SageMaker AI, Google Cloud Model Garden and Microsoft Foundry Models, and seven API platforms serve it from day one. They ship under the Muse Model License rather than an open-source licence: products must display “Built with Muse Spark Open”, and anyone selling the model as a hosted service with more than $20 million in revenue over twelve months needs a separate agreement with Meta first.
This market exists because launch announcements are easy to make and hard to grade. Press releases describe what a company intends to ship; they rarely come back later to say whether it shipped. AI Rank Bank pulls one checkable sentence out of the coverage — the sentence above — gives it a date, and lets readers price it in public. The launch itself stays with its publisher; what lives here is the claim, the crowd's call, and eventually the receipt.
How this claim is judged
Judging criteria, fixed when the market opened: Delivered if, at the check time, the Muse Spark Open weights remain publicly downloadable from the listed model hubs under the Muse Model License (including the “Built with Muse Spark Open” display requirement and the separate-agreement clause for hosted services above $20 million in twelve-month revenue), and the model remains listed by the seven named API platforms. The weights having been withdrawn, moved behind a closed release, or the licence replaced does not count.
The source of record is the publisher's own page linked above. A claim about a company's product is judged against that company's public output — its product pages, documentation, changelogs and official posts — not against rumors or third-party summaries. Only yes-or-no outcomes count: partial credit is not a verdict, and a claim that needs a paragraph of excuses has already answered itself.
How readers called it
1 reader called this claim. 100% said it would deliver.
1 Will deliver · 0 Won't ship
Points reward being right against the crowd. A correct call pays 100 × (1 − the share of readers who agreed with you when you placed it), with a floor of 10: side with a 90% consensus and a win pays 10, stand alone and a win pays up to 100. Wrong calls pay nothing. The price is locked in when the call is placed, so early readers are paid for judging before the crowd forms, not for copying it.
How readers split
Share of readers saying “will deliver”: opened at 100%, now at 100%. 4 snapshots on record since 2026-10-17 — a snapshot lands whenever a call is placed, and at least hourly while the market is open.
Verdict
No verdict yet. This claim is checked on 2026-10-20 08:00 Eastern Time (12:00 UTC) against the source of record below. When the check happens, one of three stamps lands on this page permanently: delivered if the claim came true as stated, busted if it did not, or unproven if the date passes without public evidence either way. Unproven claims pay no points and do not count against any reader's hit rate.
About this market
AI Rank Bank is an AI news front page with a memory. Every launch on the homepage carries one claim like this one, with a check date. Readers call claims with points, build a public record, and climb the leaderboard. Companies build a record too: every settled claim lands on the company's bank page, where its delivery rate is simple arithmetic that nobody gets to edit afterwards. There is no money in the market — points buy bragging rights only, which keeps the incentives pointed at being right.