Reply To: How to tag individual files on upload to S3?
I discovered the issue here. Assuming this is the form you’re having trouble with, it’s currently using the Direct to S3 uploader. However, the Direct to S3 Uploader doesn’t currently support customizing the upload parameters.
This is an issue we will certainly fix, and you can expect an update this week. In the meantime, you can use a standard Gravity Forms File Upload field. The snippet I provided before will work with that field type. Once we release the update, your snippet will work for both field types, so no additional work will be needed.