Reflection releases Beam, a 501B open-weights MoE under Apache 2.0
Beam is Reflection's first open model: 501B total and 23B active parameters, 1M-token context, under Apache 2.0.
Tagged code-model
JetBrains releases Mellum2.1 Thinking, a 12B coding MoE with 2.5B active, under Apache 2.0
Mellum2.1 Thinking is a 12B mixture-of-experts reasoning model with 2.5B active, retrained mostly with reinforcement learning on real repositories.
Z.ai releases GLM-5.3, a 753B open-weights model aimed at coding and cyber tasks
GLM-5.3 reuses the GLM-5.2 base with new post-training. The weights are public under a custom glm-5.3 licence.