Photoshop png Upload

[Filmbildfabrik]

Hi there, 

Does anyone know by chance how I can save an image with a transparent background in Photoshop and then upload it to Stock?
A png is not accepted as a file format. So what format do I save?

[Abambo]

Simple and disappointing answer: you can't, stock does not allow for images with an alpha channel 😞 !

(moving this to the stock contributor forum)