SFT Drives Gemini’s Safety Properties

Google DeepMind researchers found that supervised fine-tuning (SFT), not reinforcement learning, drives most safety properties in Gemini models. Comparing SFT-only versions of Gemini 3.1 Pro and Gemini 3 Flash to production models showed near-identical safety benchmark performance. The team plans to focus safety interventions on SFT in future Gemini versions.