Ask HN: Does Google Index “Secret” URLs Only Shared Through Gmail?
I am seeing files I upload to S3 in Google search results. I am not sure how Google found the URLs to these files as I've only shared them in email (Gmail).
I (kind-of) doubt that they found the files through your e-mail, but the files in your S3 bucket are technically available for indexing since you don't have a robots.txt.