Reflection's 501B open-weight Beam scores 90.5 on GPQA Diamond, with Apache 2.0 weights planned

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Reflection positions Beam as a Western entry in the open-weight frontier, and it is the company's first open-weight model. It is a sparse MoE with 501B total and 23B active parameters, aimed at coding, reasoning and agentic work.

Here's what changed:

• On GPQA Diamond, Beam scores 90.5, against 91.2 for GLM 5.2, 91.7 for GLM 5.3, 93.5 for Kimi K3 and 90.9 for DeepSeek V4.1 Flash.
• On SWE-Bench Verified, it hits 80.9, ahead of Inkling (77.6) and Nemotron 3 Ultra (70.7).
• Reflection plans to release the weights under Apache 2.0, with tools for running, evaluating and fine-tuning.
• Reflection pitches inference efficiency over raw capability, with 23B parameters active.

One catch: Beam is text-only, and there are no API details or pricing yet.

Why care? A planned permissive license and a small active footprint make it one to watch for self-hosted coding work.

Try it: join Reflection's early access waitlist.

Sources: reflection.ai