IBM Launches Granite 4.0: Open-Source LLMs with Hybrid Architecture

IBM launched Granite 4.0 on October 2, 2025, an open-source family of LLMs built on a hybrid Mamba/transformer architecture for greater efficiency. With reduced memory needs and lower hardware costs, the models run on affordable GPUs. Released under Apache 2.0 and ISO 42001 certified, Granite 4.0 is available via watsonx.ai and partners. Variants like Granite-4.0-H-Small (32B) rival larger competitors, with testing from EY and Lockheed Martin.