Robin Rombach

Rombach was born in Freiburg, Germany. From 2013 to 2020 he studied physics at Heidelberg University, then began doctoral research in computer science in the university’s computer vision group, working on AI-based image generation.⁠[1][2]

In 2021 he moved with his research team to Professor Björn Ommer’s computer vision lab at LMU Munich.⁠[2][1]

On December 20, 2021, Robin Rombach, as first author with Andreas Blattmann, Dominik Lorenz, Patrick Esser and Björn Ommer, posted the paper “High-Resolution Image Synthesis with Latent Diffusion Models” on arXiv, introducing latent diffusion models; the paper was revised on April 13, 2022, and presented as an oral at CVPR 2022.⁠[3][4]

Building on this work, the CompVis group released Stable Diffusion, a latent text-to-image diffusion model; its README says the model was made possible by a collaboration with Stability AI and Runway, with Stability AI donating compute, and that it was trained on a subset of LAION-5B. Andreessen HorowitzAndreessen HorowitzAndreessen Horowitz (a16z) is a venture capital firm founded in 2009 by Marc Andreessen and Ben Horowitz. It invests from the seed stage through the growth stage and provides operational support to its portfolio companies.Open the full entry describes Rombach as one of the original co-creators of the Stable Diffusion series of models.⁠[4][5]

Rombach then joined London-based Stability AI, bringing part of his research team with him, and served as a research lead there for two years; with Andreas Blattmann, Patrick Esser and others he helped develop the Stable Diffusion models at Stability AI.⁠[1][2][6]

On December 20, 2023, Andreessen Horowitz released the a16z podcast episode “Text to Video: The Next Leap in AI Generation,” in which Anjney MidhaAnjney MidhaAnjney Midha is an entrepreneur, investor, and researcher, the founder of AMP, and a visiting scientist in applied physics at Stanford University. He co-founded Ubiquity6, led developer platform ecosystem work after the company was acquired by Discord, joined Andreessen Horowitz in 2023 to work on AI investing, and currently serves at the firm as a Venture Partner.Open the full entry talked with Rombach and Andreas Blattmann about text-to-video technology; the episode page now introduces both as cofounders of Black Forest Labs. The episode was uploaded to the a16z YouTubeYouTubeYouTube is Google’s video-sharing and creator platform, founded in 2005 by Steve Chen, Chad Hurley, and Jawed Karim and acquired by Google in 2006. Built around video uploading, viewing, and creator earnings, the platform has developed Shorts, YouTube Music, Premium, YouTube TV, and products for children, and is headquartered in San Bruno, California, United States.Open the full entry channel on February 17, 2024.⁠[7][8]

The conversation centered on Stable Video Diffusion, an open-source generative video model released in November 2023, and covered the backstory of Stable Diffusion, diffusion versus autoregressive models, the benefits of single-step sampling, what video models reveal about physics, dataset selection and training, structural consistency and 3D objects, LoRAs, open challenges in video generation and the infrastructure needed for future research.⁠[7]

In March 2024 Rombach founded Black Forest Labs in Freiburg with Andreas Blattmann and eight other researchers; the ten-person founding team also included Jonas Julius Müller, Sumith Kulal, Tim Dockhorn, Axel Sauer, Dominik Lorenz, Patrick Esser, Frederic Boesel and Harry Saini. Rombach became CEO.⁠[1][2]

On August 1, 2024, Black Forest Labs announced its launch, describing its team as the creators of VQGAN, Latent Diffusion, Stable Diffusion, Stable Video Diffusion and Adversarial Diffusion Distillation; it had closed a $31 million seed round led by Andreessen Horowitz, with follow-up investment from General CatalystGeneral CatalystGeneral Catalyst (GC) is an investment firm founded in 2000 and headquartered in San Francisco, United States, created by Joel Cutler, David Fialkow and Bill Fitzgerald, that backs companies from the seed stage through growth.Open the full entry and MätchVC and angel investors including Garry TanGarry TanGarry Tan is a Canadian-born ethnically Chinese technology entrepreneur, product design and engineering practitioner, and venture capitalist who currently serves as president, CEO, and general partner of Y Combinator. He worked on early product and engineering at Palantir, co-founded Posterous, Posthaven, and Initialized Capital, led early investments in companies including Coinbase, and has long been involved in San Francisco local public affairs.Open the full entry, Brendan Iribe and Michael OvitzMichael OvitzMichael Ovitz is an American Hollywood agent and businessman, a co-founder of the talent agency Creative Artists Agency (CAA), which he chaired from 1975 to 1995, and was once regarded as one of the most powerful figures in Hollywood. He briefly served as President of The Walt Disney Company from 1995 to 1996, and his severance gave rise to shareholder litigation lasting nearly a decade; he later headed Artists Management Group and turned to technology investing and advisory work.Open the full entry. It released three versions of its text-to-image model FLUX.1, [pro], [dev] and [schnell], the last under the Apache 2.0 license.⁠[9]

Andreessen Horowitz wrote in its investment post the same day that Rombach leads Black Forest Labs together with Patrick Esser and Andreas Blattmann. The company is headquartered in Freiburg, with a second location in San Francisco.⁠[5][10][2]

On December 1, 2025, Black Forest Labs announced a $300 million Series B at a $3.25 billion valuation, co-led by Salesforce VenturesSalesforce VenturesSalesforce Ventures is Salesforce’s corporate venture capital arm. Active since 2009, it backs companies from seed through growth across enterprise software, cloud infrastructure, data, security and AI. Salesforce supplies all of its capital.Open the full entry and Anjney Midha’s AMP, with participation from Andreessen Horowitz, NVIDIANVIDIANVIDIA is an American semiconductor and computing technology company that provides graphics processing units, artificial intelligence infrastructure, networking interconnects, and computing software, and is listed on Nasdaq under the ticker NVDA.Open the full entry, Northzone, Creandum, Earlybird VC, BroadLight Capital, General Catalyst, Temasek, Bain Capital Ventures, Air Street Capital, Visionaries Club, Canva and Figma Ventures. The company had raised more than $450 million in just over a year and had a team of about 50 across Germany and the United States; the week before the announcement it released FLUX.2, its second-generation image model.⁠[6][11]

As co-founder and CEO, Rombach said, “We built Black Forest Labs to advance visual intelligence at the frontier,” adding that “Visual AI is shifting from impressive image generation to genuine understanding.”⁠[11]

In the 2026 location campaign of the IHK Südlicher Oberrhein, Rombach said of operating in Germany and the United States: “Die Amerikaner sind sehr gut darin, zu skalieren und Produkte zu entwickeln.” and “Wir wollen die Stärken beider Kontinente verbinden.”⁠[1]

Speaking to Germany Trade & Invest, he said: “I am deeply convinced that you don't need to only be in a major tech hub to execute and build a company.”⁠[2]

Black Forest Labs: Official website: https://bfl.ai/ (opens in a new window).⁠[10]