From the 2025 Report on Copyright and Artificial Intelligence [1]:
> The Office concludes that, given current generally available technology, prompts alone do not provide sufficient human control to make users of an AI system the authors of the output. Prompts essentially function as instructions that convey unprotectible ideas. While
highly detailed prompts could contain the user’s desired expressive elements, at present they do not control how the AI system processes them in generating the output.
Again, that seems to be talking about fully AI generated work, like “works created solely by machines” from the previous document, not AI-aided work. It is only stating that the prompt is not considered sufficient human work because it comes before the generation process, but it says nothing of subsequent editing of combining with other stuff.
> The Office concludes that, given current generally available technology, prompts alone do not provide sufficient human control to make users of an AI system the authors of the output. Prompts essentially function as instructions that convey unprotectible ideas. While highly detailed prompts could contain the user’s desired expressive elements, at present they do not control how the AI system processes them in generating the output.
[1] https://www.copyright.gov/ai/