How does PDF SignCheck verify a PDF digital signature?

PDF SignCheck cryptographically validates the digital signatures embedded in PDF documents. It checks that the document has not been tampered with after signing, verifies the signer's certificate chain against trusted root Certificate Authorities (CAs), and outputs a stamped PDF with a "Verified ✓" badge — similar to clicking "Trust this certificate" in Adobe Acrobat.

Is my PDF document stored or saved during digital signature verification?

No. Your file is processed entirely in memory on the server. It is never written to disk, never stored in any database, and is discarded immediately after the verified PDF is returned to your browser. We take privacy seriously — your documents remain yours.

What types of PDF digital signatures and certificates are supported?

PDF SignCheck supports PDFs that contain PKCS#7 / CMS digital signatures — the standard used by government portals, official certificate authorities, and digital signing platforms. This includes documents from DigiLocker, e-District, MCA, UIDAI, and similar government services worldwide.

Why does Adobe Acrobat Reader display a PDF signature as "Not Verified"?

Adobe Acrobat only trusts certificates from its own Adobe Approved Trust List (AATL). Many government and institutional signers are not on that list. Our tool auto-trusts the signer's certificate after cryptographic verification — exactly what Adobe asks you to do manually when you click "Trust this certificate." The downloaded verified PDF includes a visual stamp so it's clear the signature has been validated.

Is the online PDF signature verification process cryptographically secure?

Yes. We perform full PKCS#7 signature verification: we extract the signed hash from the signature, independently compute the hash of the document's byte ranges, and compare them. We also validate the certificate chain up to a trusted root CA from the Mozilla CA trust store. This is the same process that Adobe Acrobat and other professional PDF tools use.

Are there daily or rate limits for PDF cryptographic verification?

To prevent abuse, we rate-limit to 10 requests per minute per IP address. The maximum file size is 50 MB. These limits are sufficient for normal usage. If you need higher throughput for enterprise use, please contact us.

Which Indian government certificates and portals are supported?

PDF SignCheck fully supports digital signature verification for official Indian government certificates. This includes UIDAI Aadhaar Cards, state e-District certificates (such as Caste, Income, Domicile, and Birth/Death certificates), DigiLocker-issued PDF documents, NFSA Ration Cards, Income Tax / PAN documents, and any official PDF signed via CCA India (Controller of Certifying Authorities) root credentials.

How do I resolve the "Signature Not Verified" or "Signature Not Checked" warning on Aadhaar or Caste certificates?

Simply upload your signed PDF to PDF SignCheck. Our system extracts the digital signature, cryptographically validates the hash integrity against trusted root certificates, and generates a stamped PDF. When you download this verified document, the signature will show as valid, making it suitable for direct submission.

Legal Information

Legal Disclaimer

Last updated: July 2026

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Independent Service Notice

PDF SignCheck (pdfsigncheck.com) is an independent software tool developed and operated by MHQ Softech. It is not affiliated, endorsed, authorized, or associated with UIDAI, DigiLocker, Income Tax Department of India, any Indian State Government e-District portal, or any foreign government authority.

1. Nature of the Verification Service

PDF SignCheck provides automated cryptographic verification of PKCS#7 / CMS digital signatures embedded inside PDF documents according to ISO 32000 specifications and public key cryptography standards (RFC 5652).

The validation results displayed by PDF SignCheck reflect whether the electronic cryptographic hash signature embedded in the PDF binary matches the document bytes and validates against public Certificate Authority (CA) root stores. PDF SignCheck does not independently audit external government registration databases or issue legal certificates on behalf of government agencies.

2. No Legal Advice or Government Guarantee

The information, step-by-step guides, and technical explanations on this website are provided for informational and educational purposes only. While our platform verifies signature validity under standards such as the Information Technology Act 2000 (India), eIDAS (European Union), and ESIGN Act (United States), PDF SignCheck does not constitute formal legal counsel.

For official authentication or disputing government certificate rejections, users should contact the issuing state department or Certifying Authority (CA) directly.

3. Privacy & Zero-Retention Warranties

PDF SignCheck operates on a strict zero-retention architecture. PDF files uploaded for verification are processed in volatile system memory (RAM) and immediately garbage-collected after the verified document is generated. We do not store, copy, archive, or transmit your document contents to third-party databases.

4. Trademark & Intellectual Property Disclaimers

All trademarks, product names, logos, and brands referenced on this site (including Adobe, Adobe Acrobat, DigiLocker, Aadhaar, UIDAI, DocuSign, Singpass, UAE Pass) are the property of their respective owners. Their mention on PDF SignCheck is solely for descriptive purposes to identify compatible document formats and signing workflows under nominative fair use.

5. Contact & Support

If you have questions regarding this Legal Disclaimer, please email us at: hi@pdfsigncheck.com