Skip to content

Invest Also reported elsewhere2 publishers 2 min read Published

Reflection AI says Beam reaches GLM-5.2 reasoning scores on 3-4x less inference compute

Reflection AI said it will release the weights for Beam, a 501-billion-parameter open model with 23 billion active, later this month. Red-teaming is unfinished, so every score so far is the company's own.

The Investor · Invest desk

Send a correction

Illustration accompanying Reflection AI says Beam reaches GLM-5.2 reasoning scores on 3-4x less inference compute
Generated illustration
Beam is sparse, with a high-compute RL run behind it Beam's model size and training scale, as Reflection reports them in its blog post announcing the model.

Figures Reflection reported for Beam: 501 billion total parameters, 23 billion of them active; pretraining on 23.8 trillion tokens; an RL run on 10.5K Nvidia GB300 GPUs over 4 weeks that generated over 100 million rollouts; and approximately 1.3 billion sandboxes used for training and grading.

Beam is sparse, with a high-compute RL run behind it
FigureValueNoteClaim
Total parameters501 billion23 billion active1
Pretraining tokens23.8 trillion2
GPUs in the RL run10,500 Nvidia GB300sover 4 weeks, over 100 million rollouts3
Training and grading sandboxes1.3 billionapproximately4

What happened

  • Reflection describes Beam as a sparse mixture-of-experts model built for coding, reasoning and agentic workloads, and as the company's first open-weight release.
  • Reflection's reinforcement-learning run generated more than 100 million rollouts on 10.5K Nvidia GB300 GPUs over four weeks.
  • Reflection says Beam is competitive with larger open models like GLM 5.2 and approaching Qwen 3.8-Max on coding and agentic tasks.
  • Daily Upside reported that Nvidia was among the investors in a $2 billion round last year that valued Reflection at $8 billion.

Why it matters

  • What it limits constraint In the text of Reflection's post, every named comparison is to an open model, so a builder weighing Beam against a closed frontier API has to run that test once the weights ship.
  • What it costs cost The RL run alone was about 7.06 million GPU-hours, so each $1 of hourly GPU price adds about $7 million to its cost. Reflection did not disclose the rate it paid.
  • Who's exposed exposure The $25 billion round the Wall Street Journal reported Reflection discussing would be half of Moonshot's $50 billion valuation, and Moonshot and DeepSeek are both heading to IPOs.
  • Who has to decide decision Teams that want a non-Chinese open-weight option, the buyer Daily Upside describes, now have a candidate to schedule evaluations for, but any commitment waits on the weights.

We think the efficiency claim is the one to test and the capability claim is the one to take at Reflection's word, because the company concedes the capability point itself. Its post says frontier open models like Kimi K3 remain ahead on raw capability and that Beam's advantage is efficiency at inference time [18]. The design agrees. Beam has 501 billion parameters [1] against a 2T-plus family for Qwen 3.8-Max [20], so it is about a quarter of that size or less [22], and only 23 billion are active, or 4.6% of the total [12].

Taken at face value, 3-4x less inference compute than GLM-5.2 at comparable advanced-reasoning scores [19] puts Beam at a quarter to a third of the compute [23], or rather puts it there on the benchmarks Reflection reports. The weights are still unreleased [16]. The post shows per-benchmark results in a figure, with NR marking scores that have not been reported [6].

Pretraining points the same way. Reflection used 23.8 trillion tokens [2], about 1,035 for each active parameter [13]. Training cost is paid once and serving cost on every request. In our view, that ratio assumes total serving spend will exceed training spend.

The counter-case is cost per task. Daily Upside cites a study of 6,800 tasks from researchers at Stanford, Carnegie Mellon, Berkeley and Microsoft in which cheaper models cost more than expensive ones on a third of tasks, because they took longer and sometimes failed [21]. Reflection's design answers part of that: it trained with a controllable length penalty and offers a reasoning effort setting where lower values favor shorter responses [5].

Either outside runs reproduce the compute ratio, and builders get a cheaper reasoning option from a US lab. Or the saving narrows once completions lengthen. Reflection says they fell early in reinforcement learning and grew again as agentic skills developed [7]. The post's text ties the 3-4x figure to advanced reasoning benchmarks [19]. Or the release slips past the month Reflection named [16]. We put most weight on the second.

What to watch

  • Whether Reflection posts the weights, technical report and model card by the end of this month, as its post promises.
  • Third-party results for Beam against GLM-5.2 at several reasoning effort settings, measured in cost per solved task.
  • Whether the reported $25 billion round closes, and at what valuation against Moonshot's $50 billion.

Information, not investment advice. This story is general information about companies and markets, drawn from cited reporting. It is not a recommendation to buy, sell or hold any security; check the cited sources before acting.

Clarity's read

What the record supports and how the coverage leans. The claims behind it follow.

Reality

Evidence35
Adoption
Not scored
Hype gap+30
Incentives75
Confidence55
Why these scores

Claim ledger

Ranked by verification strength, evidence, and original report placement.

  1. [1]

    Beam is Reflection's first open-weight model, a sparse Mixture-of-Experts model with 501 billion total parameters and 23 billion active, built for coding, reasoning, and agentic workloads.

    Reported Supported Source: Reflection AI blog post, reflection.aiView cited source
  2. [2]

    Reflection pretrained Beam on 23.8 trillion tokens from the web and proprietary licensed datasets.

    Reported Supported Source: Reflection AI blog post, reflection.aiView cited source
  3. [3]

    Reflection's high-compute RL run generated over 100 million rollouts on 10.5K NVIDIA GB300 GPUs over 4 weeks of training.

    Reported Supported Source: Reflection AI blog post, reflection.aiView cited source
  4. [4]

    Beam's training and grading used approximately 1.3 billion sandboxes, drawn from one million coding, agentic and STEM environments.

    Reported Supported Source: Reflection AI blog post, reflection.aiView cited source
  5. [5]

    Reflection trained Beam with a controllable length penalty, and users control the capability-versus-tokens tradeoff through a reasoning effort parameter where lower settings favor shorter responses.

    Reported Supported Source: Reflection AI blog post, reflection.aiView cited source
  6. [6]

    A figure in the post shows Beam's performance across coding, agentic, reasoning and STEM benchmarks, with NR denoting scores that have not been reported.

    Reported Supported Source: Reflection AI blog post, reflection.aiView cited source
  7. [7]

    Early in RL, performance improved as completion lengths fell; later, as Beam developed stronger agentic capabilities, completion lengths grew again, with the additional tokens supporting further gains.

    Reported Supported Source: Reflection AI blog post, reflection.aiView cited source
  8. [8]

    Nvidia was among the investors in a $2 billion funding round last year that valued Reflection at $8 billion.

    Reported Supported Source: Daily Upside, thedailyupside.comView cited source
  9. [9]

    The Wall Street Journal previously reported that Reflection has held talks this year for another fundraising round that would value it at $25 billion.

    Reported Supported Source: The Wall Street Journal, as reported by Daily UpsideView cited source
  10. [10]

    Moonshot closed a fundraising round that valued it at $50 billion, according to Bloomberg, and is heading to an IPO in early 2027; DeepSeek is nearing a new round of at least 80 billion yuan ahead of a planned IPO next year.

    Reported Supported Source: Bloomberg, as reported by Daily UpsideView cited source
  11. [11]

    Daily Upside frames Beam as news for domestic AI users who do not want to pay for costly closed frontier models and do not want to rely on a Chinese open-weight ecosystem.

    Reported Supported Source: Daily Upside, thedailyupside.comView cited source
  12. [12]

    Beam's active parameters are about 4.6% of its total.

    Derived Supported
  13. [13]

    Pretraining used about 1,035 tokens per active parameter.

    Derived Supported
  14. [14]

    The RL run was about 7.06 million GPU-hours, so each $1 of hourly GPU price adds about $7 million.

    Derived Supported
  15. [15]

    The $25 billion valuation Reflection reportedly discussed is half of Moonshot's $50 billion.

    Derived Supported
  16. [16]

    Beam is undergoing final red-teaming and evaluations, and Reflection will release the weights, technical report, model card and developer artifacts later this month.

    Reported Insufficient Source: Reflection AI blog post, reflection.aiView cited source
  17. [17]

    Reflection says Beam is competitive with larger open models like GLM 5.2 and approaching Qwen 3.8-Max on coding and agentic tasks.

    Reported Insufficient Source: Reflection AI blog post, reflection.aiView cited source
  18. [18]

    Reflection says frontier open models like Kimi K3 remain ahead on raw capability, and that Beam's advantage is efficiency at inference time.

    Reported Insufficient Source: Reflection AI blog post, reflection.aiView cited source
  19. [19]

    On advanced reasoning benchmarks, Reflection says Beam achieves scores comparable to GLM-5.2 while using 3-4x less inference compute.

    Reported Insufficient Source: Reflection AI blog post, reflection.aiView cited source
  20. [20]

    Models in the 2T+ parameter family, like Qwen 3.8-Max, require significantly more inference compute per token, according to Reflection.

    Reported Insufficient Source: Reflection AI blog post, reflection.aiView cited source
  21. [21]

    A study spanning 6,800 tasks by researchers at Stanford, Carnegie Mellon, Berkeley and Microsoft found cheaper models ended up costing more than more expensive models for one-third of tasks because they took longer and sometimes ended in failure.

    Reported Insufficient Source: Daily Upside, summarizing the studyView cited source
  22. [22]

    Beam's 501 billion parameters are about a quarter or less of a 2 trillion-parameter model.

    Derived Insufficient
  23. [23]

    3-4x less inference compute means Beam uses a quarter to a third of GLM-5.2's compute on the reported benchmarks.

    Derived Insufficient

Sources

2 independent publishers whose own reporting we read for this story.

  1. reflection.ai

    1 article · October 11, 2026

    Reflection AI
  2. thedailyupside.com

    1 article · October 11, 2026

    Reflection Wants to Deliver America’s Most Powerful Open-Weight AI

Topics and entities