How to Prevent Missing Text, Signatures, or Stamps in Mailed PDFs

Some PDFs (especially fillable forms and e-signed documents like DocuSign) can look correct on screen, but lose important content during printing/production unless they are flattened . This guide explains what flattening means, why it matters, and how to do it on Windows and Mac.

PDF Forms (fillable fields) DocuSign / eSign stamps Signatures & timestamps Annotations & overlays Court-safe printing

What does “Flattening” mean?

Quick definition

Flattening means converting a PDF so that everything you see on the page (typed form fields, signatures, stamps, and timestamp text) becomes a permanent part of the PDF page content—like ink printed on paper.

Why it matters: Fillable fields and e-sign elements are often stored as annotations or form layers . Some printing pipelines remove or ignore these layers, which can cause signature text, timestamps, or entered form data to disappear.

Common “high risk” PDFs

Fillable PDF forms (AcroForms)
DocuSign / eSign PDFs with signature blocks or envelope IDs
PDFs where text was added using an “Edit PDF” feature
PDFs created by combining multiple sources or scans

What you might see

PDF preview looks correct
But printed/processed copy is missing typed information
Signature stamps or timestamps disappear
Only some pages are affected (often the last page)

How to Flatten a PDF (Windows)

No paid tools required

Method A (Recommended): Print to PDF

Open the PDF using Adobe Acrobat Reader (free) or your PDF viewer.
Click File → Print .
Select printer: Microsoft Print to PDF .
Choose Actual size or 100% (avoid “Fit to page” if possible).
Click Print and save the new file.

The newly saved PDF is flattened and is the safest version to upload for mailing.

Tip: Name the file something like Document-FLATTENED.pdf so you know you uploaded the correct version.

How to Flatten a PDF (Mac)

Quick & easy

Method A (Recommended): Print to PDF from Preview

Open the PDF in Preview (default Mac app).
Click File → Print .
In the bottom-left of the print dialog, click PDF → Save as PDF .
Save the new file.

This creates a flattened version where fillable fields and overlays become permanent.

Flattening with Adobe Acrobat Pro (Best Option)

Highest quality

If you have Adobe Acrobat Pro , flattening can preserve the highest quality and formatting.

Open the PDF in Adobe Acrobat Pro.
Go to Tools → Print Production .
Select Flatten Preview .
Click Apply , then save the file.

If you do not see “Print Production”, you may be using the free Reader version.

DocuSign / eSign Documents: Important Note

Very common issue

DocuSign and other eSign providers often add signatures, timestamps, and envelope IDs as annotations . These elements may appear correctly on screen but can be removed during printing if the PDF is not flattened.

Recommendation: After you download a completed DocuSign/eSign document, flatten it using “Print to PDF” before uploading for mailing.

How to Tell If Your PDF Might Not Be Flattened

Quick checks

Check #1 (Simple)

If you can click on a signature/timestamp and it highlights like a separate object, it may be an annotation/form layer and should be flattened.

Check #2 (Fillable form)

If the PDF has fields you can type into (name, date, checkbox), it’s a fillable form. Fill it out, then Print to PDF to flatten before uploading.

Need Help? We Can Flatten It For You

Get Support

If you’re unsure whether your PDF is properly flattened, you can reach out to us at support@casemail.us . We can help confirm the issue and, if needed, we can flatten the PDF for you before you resubmit it.

Please contact CaseMail Support and include your CaseMail ID / Job ID (if applicable).

Important: Flattening is recommended any time you:

Fill out a PDF form
Add text to a PDF after signing
Use DocuSign/eSign stamps, signature blocks, timestamps, or envelope IDs

FAQ

Common questions

Will flattening change my document?

Flattening should not change the visible appearance of your document. It simply makes the content permanent so it prints reliably. We recommend using “Actual size / 100%” when printing to PDF to avoid scaling changes.

Why did my PDF look fine during preview/validation but fail later?

Many PDF previews display annotation and form layers correctly. But some production printing pipelines remove those layers. Flattening ensures the content becomes part of the page itself.

Is this only a CaseMail issue?

No. This can happen across many platforms that process PDFs for printing. Flattening is a best practice anytime you use forms, signatures, or stamps that are not permanently embedded.