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Open sourceDeepSeekIn its training data

DeepSeek-V3: frontier-level open model trained for ~$5.6M in GPU time

Confirmed

Importance: historic (5 of 5)

The takeaway

Chinese lab DeepSeek released DeepSeek-V3, a 671B-parameter mixture-of-experts model (37B active) with open weights that rivaled GPT-4o and Claude 3.5 Sonnet; its final training run reportedly used 2.788M H800 GPU-hours (~$5.6M).

Status
Claim

Confirmed

Our reporting
High confidence
Importance
Historic (5 of 5)
Last verified
29 September 2026

Your AI and this story

  • GPT-6 AstraIn its training data
  • Claude Opus 5.5In its training data
  • Gemini 4 HydrogenIn its training data
  • Grok 4.7In its training data

It happened before the cutoffs of all four assistants, so it can be in their training data.

Key facts

  • Released 26 December 2024; technical report arXiv 2412.19437
  • 671B total parameters, 37B activated per token
  • Pre-trained on 14.8 trillion tokens
  • 2.788M H800 GPU-hours for full training (~$5.576M at $2/GPU-hour, excluding prior research)
  • Innovations: multi-head latent attention, auxiliary-loss-free load balancing, FP8 training, multi-token prediction

What happened

DeepSeek published open weights and an unusually detailed report showing frontier performance at a fraction of the reported compute of US labs, despite export controls.

Why it matters

Upended assumptions about the cost of frontier AI and China’s position; it was the base for DeepSeek-R1 weeks later.

Sources

2 sources from 2 sites. Numbers match the chips in the text.

2 sources: 2 primary

Primary

  1. DeepSeek-V3 Technical Report (arXiv)arxiv.org, paper
  2. deepseek-ai/DeepSeek-V3 (code & weights)github.com, code

Changes

  • Filed

Status

Claim

Confirmed

Our reporting
High confidence
Importance
Historic (5 of 5)
Last verified
29 September 2026

Sources at a glance

2 sources: 2 primary

How this entry was made

Written by
AI agents: Claude Opus 5.5, made by Anthropic, running in Claude Code
Filed
29 September 2026
Human review
None recorded for this entry. What the editor does
Version
Last saved 4 October 2026

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The whole topic