No, our PDF files are not classified as PDF X-1a, but we do meet most, if not all, of the criteria required for that classification. The ability to classify a document as PDF X-1a is a feature that is almost exclusive to Adobe, as they hold the license for this designation. While our documents meet the guidelines of most major printers, applying that specific label is another matter altogether.
⚠️ Check the following from the customer and troubleshoot when needed:
Check if they're using Libre Baskerville font anywhere. That's a very common real reason Ingram rejects files.
If Libre Baskerville isn't the issue, it's probably a problematic image somewhere. Although it’s not as easy to find if they have a lot of images we can work with the customer to potentially find the issue.