Grok-1
xAI open-sources Grok-1, a 314B-parameter Mixture-of-Experts base model, making it the largest openly released LLM at the time of publication.
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MoE at 314B: The architecture activates 25% of weights (~86B active parameters) per token, positioning Grok-1 between dense 70B models and proprietary trillion-parameter systems.
Base model release: xAI releases the raw base model weights and network architecture under Apache 2.0 - no instruction tuning, no RLHF, intentionally leaving fine-tuning to the community.
Training data cutoff: Pretraining uses a corpus with an October 2023 knowledge cutoff, so downstream fine-tunes inherit roughly 1-year-old world knowledge.
Openness signal: The release significantly raises the bar for "open" large-model weights and pressures other labs, coming shortly before Elon Musk's public criticism of OpenAI's closed approach.