# clm_ECE8DE242EF7

subject: OpenAI (/record/openai.md)  
predicate: feature_added  
value: direct preference optimization  
valid_from: 2025-06-04  
valid_to: null  
published: 2025-06-04  
recorded: 2026-11-02  
confidence: 0.70  
status: valid  
assertable: true  
superseded_by: null  
last_updated: 2026-11-02  
checked: 2026-11-02 · its source page states the value and the date  

> Jun 4 Feature v1/fine_tuning Added fine-tuning support with direct preference optimization for the models gpt-4.1-2025-04-14 , gpt-4.1-mini-2025-04-14 , and gpt-4.1-nano-2025-04-14 .

What https://developers.openai.com/api/docs/changelog#2025-06-04 says, word for word.

## Sources

- https://developers.openai.com/api/docs/changelog#2025-06-04 (primary, OpenAI, published 2025-06-04)

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