The Ministry of Corporate Affairs (MCA) manages the registration and regulation of companies and LLPs in India through its MCA21 portal. Documents issued via MCA21 — including your Certificate of Incorporation, ROC filings, and other company registration records — are digitally signed to guarantee their authenticity. However, these signatures almost always display as "unknown" or "not valid" in standard PDF readers. Here's why, and how to verify them properly.
Certificate of Incorporation (COI): The primary proof that a company or LLP exists as a legal entity under Indian law, issued by the Registrar of Companies (ROC) via MCA21.
ROC Extract / Master Data: Public company data extracted from the MCA21 registry, showing details like CIN, date of incorporation, registered address, and director information.
Annual Filing Acknowledgements: Confirmation PDFs issued when a company files its annual returns (AOC-4, MGT-7) or financial statements with the ROC.
Director's Report and Board Resolutions: Certain MCA-generated documents related to company governance are issued with digital signatures.
All these documents are signed using MCA's own CA infrastructure, which is separate from NIC, though both operate under the CCA (Controller of Certifying Authorities) framework.
MCA operates its own Certifying Authority called the MCA21 CA. Like NIC and other Indian government CAs, MCA21 CA is not pre-installed in the Adobe Approved Trust List (AATL) or any other commercial PDF reader trust store. When Adobe Acrobat or a similar viewer encounters an MCA21 signature, it has no prior knowledge of that CA and therefore cannot confirm validity — displaying "unknown" or "not valid."
This does not mean the document is illegitimate. It is a standard, expected behaviour due to the gap between Indian government PKI and global commercial trust infrastructure.
VerifySign.in has integrated the MCA21 certificate chain into its verification engine alongside NIC and other Indian government CAs. When you upload an MCA21 document, VerifySign.in identifies the MCA21 CA signature and performs a complete cryptographic verification — confirming the document is genuine and has not been altered since it was signed.
Investor Due Diligence: Before investing in a company, investors and their legal advisors verify the Certificate of Incorporation to confirm the company's legal standing. A verified COI builds trust and speeds up the process.
Business Bank Account Opening: Banks require the COI as a KYC document. A digitally signed and verified COI may expedite account opening compared to a physical copy.
Vendor and Partner Onboarding: Companies running due diligence on potential vendors or partners will check ROC records and may request a verified MCA21 extract.
Auditor and Statutory Compliance: Company auditors require authentic corporate documents for annual audits. Verified MCA21 PDFs serve as reliable primary sources.
Step 1: Download your MCA21 document — Certificate of Incorporation, ROC extract, or filing acknowledgement — from the MCA portal (mca.gov.in).
Step 2: Open VerifySign.in.app and upload the PDF.
Step 3: VerifySign.in detects the MCA21 CA signature and verifies it against the trusted certificate chain.
Step 4: View the full verification report — signer details, MCA21 CA information, signing date, and validity status. Optionally download a verified copy with LTV embedded.
Instant digital signature verification for any government PDF — free, secure, no software needed.
Go to VerifySign.in →