On September 2, 2026, alongside the launch of Muse Spark 1.3, Meta announced a roadmap "including bigger models" (https://research.meta.ai/blog/introducing-muse-spark-1-3). Credible reporting has identified Meta's next-generation frontier model by the internal codename "Watermelon." This market will resolve according to the calendar date (ET) on which Meta's "Watermelon" model, or a model identified as the model internally codenamed "Watermelon," is made available to the general public. A qualifying model must be named "Watermelon" or be identified, by Meta or by a consensus of credible reporting, as the model internally codenamed "Watermelon," regardless of the name under which it is ultimately released. A qualifying model must be launched and publicly accessible, including via open beta or open rolling waitlist signups. A closed beta or any form of private access will not suffice. The release must either be clearly defined and publicly announced by Meta as accessible to the general public, or otherwise be made publicly accessible and explicitly labeled on the company's official website. Labeling errors, placeholder text, or version names displayed on the website that do not correspond to a model that is actually accessible to the general public will not qualify. The primary resolution source for this market will be official information from Meta, with additional verification from a consensus of credible reporting.