Mercury: Ultra-fast language models based on diffusion

Are there any rules for what can be uploaded to arxiv?

This is a marketing page turned into a PDF, I guess who cares but could someone upload like a facebook marketplace listing screenshotted into a PDF?

Yes, arxiv requires that submissions must be scientific research. And not just anyone can publish on arxiv, you need endorsement by existing users.

That that scientific research is in pursuit of a commercial product, or that the paper submitted is of low quality, is not something they would filter however.