Hi,
Our dev team finished the investigation for the signature issue. The signature in your original PDF/A file is in accordance with PDF/A standard. Because your two documents has one is in common PDF standard and the other is in PDF/A standard, we made the merged document is in common PDF standard, and the signature as below is in accordance with common PDF standard, so the result is fine when it is in common PDF standard.
common.png
If the merged document is in PDF/A standard, the signatrue will keep original PDF/A standard as below.
original.png
To keep original signature intact, the merged document must be in PDF/A standard. Please tell us whether you can accept the merged document is in PDF/A standard or not. If you can, we will do some modification to make the merged document is in PDF/A standard.
Best Regards,
Amy
E-iceblue support team
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