How do I upload multiple files

Vector graphics = .ai, .eps or .svg files only (no bitmaps allowed inside)

Include 1 .jpg preview for each vector submitted.

Raster images = .jpg  or .png (with transparency). 

Now, I realise I confused myself between AI=artificial intelligence and AI=Adobe Illustrator. It's "no PNG in Adobe Illustrator" that is the rule.

You simply can't sell “multiple files” in one listing. One asset will be one entry to stock. And if the asset is an AI file, you need to give the original AI file. That's the deal.

If you are new to stock, you should consider these resources: https://helpx.adobe.com/stock/contributor/tutorials.html
Please read the contributor user manual for more information on Adobe stock contributions: https://helpx.adobe.com/stock/contributor/user-guide.html
See here for rejection reasons: https://helpx.adobe.com/stock/contributor/help/reasons-for-content-rejection.html
and especially quality and technical issues: https://helpx.adobe.com/stock/contributor/help/quality-and-technical-issues.html

1. You are not allowed to submit a vector made from bitmaps. So, no PNG in AI.

2. Customers pay the same for each standard image, no matter what is in it.

3. Be sure you are up to date with the strict rules for submitting AI.