OmniDocCompare Two Contract Versions Before Anyone Re-Signs
Learn how to tell whether a revised signed PDF needs a new signature, and how to compare both versions in OmniDoc to confirm every change first.
A contract gets signed, and then someone returns a revised copy with a short note saying only a few small things changed. Before anyone signs again, you need to know exactly what changed, because a signature applies to one specific file. Revised PDFs rarely announce their edits, and a changed price, date or clause can hide in a page that looks the same as before.
This guide is for people who handle contracts, agreements and approvals and need to repeat electronic signature approval after a PDF has been edited. You will learn how to decide whether a new signature is needed, how to compare the signed version with the revised one in OmniDoc, and how to send the confirmed file for a sign PDF document step.
The goal is simple: no one signs a version they have not checked line by line against the list of changes.
Should you re-run electronic signature approval after a PDF changes? The short answer
Yes, re-sign whenever a term, number, date, party detail or attachment changed, and only after you have a written list of those changes.
| Your situation | What to do | Why |
|---|---|---|
| The revision fixes a typo, and both sides agreed in writing | Compare the files, confirm the list contains only typo fixes, then agree on whether to re-sign | A signature still applies to the exact file, so even small edits change what was approved |
| A price, date, quantity or scope changed | List each change, get written confirmation, then send the full revised PDF for a new signature | These terms carry the meaning of the agreement |
| Pages were added, removed or reordered | Compare page by page and confirm no clause moved or changed wording | A reordered clause can change which terms a reader thinks apply |
| You do not know who made the edit | Stop, compare against the signed copy, and ask the sender to explain each change | An unexplained edit is a reason to pause before signing |
| The PDF is a scan with no selectable text | Run OCR in the PDF editor, check the recognized text, then compare | A comparison needs readable text to find differences |
Whether a given edit requires a new signature depends on your agreement and local rules. When the stakes are high, check with your legal contact before signing.
Figure out which problem you have
Use this table to match what you see with the likely cause before you start comparing.
| Symptom | Likely cause | How to confirm |
|---|---|---|
| The revised file looks almost identical, but the other party says it changed | Edits in a clause, table cell or footnote you did not read closely | Run the comparison and review every reported difference |
| The signature block is missing or sits on a different page | Pages were inserted, removed or reordered | Compare page counts and page order in both files |
| The comparison reports no text differences, but you know something changed | The PDF is scanned, so there is no text layer to compare | Try selecting a line of text; if you cannot select it, the file is probably scanned |
| A number in a table or schedule is different | A value was changed in a cell, or a total was updated by hand | Check the cells named in the comparison and recalculate totals yourself |
| The sender calls the edit "just formatting" | Font, spacing or line-break changes that also altered wording | Compare the text itself, not just how the pages look |
Fix it step by step
- Save both versions separately. Put the signed PDF and the revised PDF in one folder with clear names, such as "signed-v1" and "revised-v2." Do not overwrite either file.
- Confirm both files have readable text. Try selecting a line of text in each PDF. If you cannot, run OCR on that file in the PDF editor in the desktop client, save the result as a copy, and check the recognized text against the page before you rely on it.
- Open the comparison. If you do not have the desktop client yet, download it from download.omnidoc.top. Use the function that compares two PDFs, loading the signed version as the original and the revised version as the new file.
- Write down every difference. Go through the results page by page. For each change, note the page, the clause or line, the old text and the new text.
- Sort each change into one of three groups. Use "formatting only" for spacing, fonts and spelling; "clarified" for new wording that keeps the same obligation; and "substantive" for price, dates, scope, parties, liability or term length. Substantive changes need a decision from the people named in the agreement.
- Look for what the comparison may not explain. Check for added or removed pages, new attachments mentioned in the text, and numbers that changed in a schedule. Confirm each one against the sender's cover note.
- Send your change list and ask for written confirmation. Ask the other party to reply in writing that the list is complete. Agree on one final version before anyone signs.
- Sign only the confirmed file. When the final version is agreed, send that exact PDF for others to sign online with OmniDoc's sign feature, or sign it yourself in the PDF editor if you are a signer. Do not sign any file that differs from the list you confirmed.
Prevent it next time
- Tie every signature to one final file. Send the agreed version for signing, and never send an earlier copy alongside it.
- Require a change note with every revision. Ask senders to list edits before they return a file, so you are not reconstructing changes after the fact.
- Put version numbers and dates on the first page. A version label makes it easy to see which copy was signed and which one is newer.
- Negotiate in an editable source, then export to PDF for signing. When the source is a word processing file, the exported PDF is the one you compare and sign.
- Keep an untouched archive copy of each signed PDF. Store it in a separate folder that no one edits, so you always have the reference version to compare against.
- Run a comparison every time a revised PDF comes back. Make it a standing step before anyone is asked to re-sign.
❓ FAQ
1. Does a typo fix always need a new signature?
Not always. The agreement and local rules decide that, so confirm the change in writing with the other party and check with your legal contact if the contract requires a new signature for any edit.
2. Can I compare a scanned contract?
Yes, once it has readable text. Run OCR on the scan first, then check the recognized text against the page before you rely on the comparison.
3. What if the revised version arrives as a Word file?
Compare the PDF versions you plan to sign. If the revision is a Word file, export it to PDF in your word processor, then compare it with the signed PDF so the file you sign is the one you checked.
4. Who should approve the final version?
The people the agreement names as signers or approvers. A comparison helps them see every change, but it does not replace their review.
📝 Summary
A revised PDF is a new document, so treat every edit as a reason to compare before anyone re-signs. Use electronic signature approval only after you have a written list of changes and a confirmed final file. Then send that exact file for signing, and keep an untouched copy of each version.
