It’s the first such models it’s launched in over five years, as pressure in the US grows to respond to China’s dominance in open models.

It’s the first such models it’s launched in over five years, as pressure in the US grows to respond to China’s dominance in open models.

Meta, Microsoft-backed Mistral and the Chinese startup DeepSeek have also released open-weight models in recent years.

The models, gpt-oss-120b and gpt-oss-20b, represent a major shift for the AI company.

Enterprises can use a powerful, near topline OpenAI LLM on their hardware totally privately and securely, without sending data to the cloud.

The verdict, for now, is split. OpenAI’s gpt-oss models are a landmark in terms of licensing and accessibility.

With safer design, more robust reasoning, expanded developer tooling, and broad user access, GPT-5 reflects a maturing AI ecosystem.