<![CDATA[Document verification requires distinguishing issuance records, file equality, and signatory identity. This study designs a PDF verification mechanism using QR codes and SHA-256 and evaluates its comparison component locally. The method combines a targeted literature search, architecture and decision-model design, and testing with 12 synthetic PDFs containing 1, 3, or 10 pages. Demonstration QR codes are embedded before PDF finalization and hashing to prevent circular hash dependencies, ensuring strict byte-level integrity verification. Seventy-two comparisons cover identical controls, text changes, numeric changes, added pages, metadata changes, and different documents carrying the same QR code. All 12 controls yield matching hashes, whereas all 60 variants yield different hashes. Extracted text remains unchanged in the metadata cases. Six status-decision cases produce the specified local outcomes. These findings support byte comparison within the tested scope while identifying its limits: scanning a QR code without submitting the PDF does not check the user-held file, and a hash does not authenticate the signatory. The Google Workspace architecture remains an undeployed design. Cloud security, network performance, and usability are not evaluated. The contribution consists of a finalization procedure, distinct verification labels, and a reproducible test package.]]>
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