Flower Labs is a 2023 University of Cambridge spinout, with offices in London and Hamburg, that maintains Flower, a widely used free, open-source framework for federated learning — training AI on data that stays where it is, such as inside hospitals or banks, instead of pooling it on one central server. It makes, or plans to make, money on top of that free code: a managed platform for running these setups (SuperGrid, opened as an early-access preview in September 2025), engineering and pilot projects for organizations, and, since 2026, its own AI models, including Endeavor, a licensed model it pitches to European buyers as a "sovereign" alternative to OpenAI and Anthropic. It has raised about $23.6 million in disclosed rounds, including a $20 million Series A led by Felicis in February 2024 at a reported $100 million valuation, and does not disclose revenue. The key risks: its claims that Endeavor matches the leading US models are self-reported and untested by outside evaluators, the model is built on existing open models (press reports name Meta and Mistral) rather than trained from scratch, its paid products are mostly offered by request or in preview, and it is unproven whether regulated buyers will pay for the control they say they want.
Timeline
Nov 3
Releases Endeavor 1.1, adding image inputs and the option to run the model on GPUs in the EU; it headlines a composite score narrowly ahead of OpenAI's GPT-5.6 Sol, but the figures are self-reported and built on tests where top models already score near the maximum.
Sep 2025
Opens early-access preview of Flower SuperGrid, a platform for setting up and managing federated-learning networks at scale and a step toward a paid product built on the free framework.
Sep 1
Launches Endeavor 1.0, a general-purpose model customers can run on their own servers, as a preview for selected organizations; Flower says it rivals OpenAI and Anthropic on some tests, while press reports say it draws on open models from Meta and Mistral and that the company expects to raise money again in about a year.
Apr 2025
With data-network startup Vana, trains Collective-1, a 7-billion-parameter language model, on GPUs spread across the internet rather than in one data center; co-founder Nic Lane tells Wired the company is training a 30-billion-parameter model and plans a 100-billion-parameter one.
Apr 15
Releases a preview of Lizzy 7B, a small open-weight model (its files are free to download) built in the UK for public-sector and enterprise use, with company-run benchmarks showing it ahead of comparable European models on most tests.
Mar 2025
Launches Flower Intelligence in preview, a service that runs AI on users' own devices and hands off to Flower's encrypted cloud when more computing power is needed; Mozilla signs on to use it for an AI summary feature in its Thunderbird email app.
Mar 2023
Launches as a company, with Y Combinator as an early backer, to commercialize the Flower open-source project; in August it announces a $3.6 million pre-seed round.
Mar 11
Red Hat and Flower Labs engineers publish an open-source add-on that lets companies deploy and manage Flower across many groups of servers through Open Cluster Management, the open-source project underlying Red Hat's cluster-management product.
Feb 2024
Raises a $20 million Series A led by Felicis at a reported $100 million valuation, with 13 employees, saying it is not yet focused on revenue and will build paid tools on top of its free framework.
