AI video startup Runway has raised $315 million in a Series E funding round, increasing its valuation to $5.3 billion, according to a source familiar with the matter. The capital will support Runway’s mission to “pre-train the next generation of world models and bring them to new products and industries,” the company said in a blog post announcing the funding. World models are advanced AI systems designed to build internal, dynamic representations of environments, enabling them to anticipate and plan for future events. Experts believe these models are crucial for advancing beyond the current limitations of large language models and achieving more general, adaptive intelligence. Runway, best known for its physics-aware video generation tools, launched its first world model in December and now sees the technology as central to solving complex challenges in medicine, climate science, energy, and robotics. While the company has long served media, entertainment, and advertising clients—including a recent collaboration with Adobe—Runway is now seeing growing interest in gaming and robotics sectors. This strategic pivot comes amid rising competition in the world model space, with rivals such as World Labs, led by Fei-Fei Li, and Google DeepMind recently releasing their own models to the public. The funding round follows the launch of Gen 4.5, Runway’s latest video generation model. Gen 4.5 enables users to create high-definition videos from text prompts and introduces native audio, long-form video generation, multi-shot sequences, character consistency, and enhanced editing features. The model has outperformed video generation systems from both Google and OpenAI on key benchmarks, a milestone that likely played a significant role in attracting investor confidence. Beyond model innovation, Runway has been strengthening its infrastructure. The company recently partnered with CoreWeave to expand its compute capacity, a move that addresses the intense computational demands of training and running advanced AI systems and may have reassured investors about its operational scalability. Looking ahead, Runway plans to rapidly grow its team of about 140 employees across research, engineering, and go-to-market functions. The round was led by General Atlantic, with participation from major tech and investment firms including Nvidia, Fidelity Management & Research, AllianceBernstein, Adobe Ventures, Mirae Asset, Emphatic Capital, Felicis, Premji, and AMD Ventures.