# Impact Statement (archived; not in IEEE Access submission) Auditor signatures on financial reports are a key safeguard of corporate accountability. When the signature on an audit report is produced by reproducing a stored image instead of by the partner's own hand---whether through an administrative stamping workflow or a firm-level electronic signing system---this safeguard is weakened, yet detecting the practice through manual inspection is infeasible at the scale of modern financial markets. We developed a pipeline that automatically extracts and analyzes signatures from over 90,000 audit reports spanning a decade of filings by publicly listed companies in Taiwan. Combining deep-learning visual features with perceptual hashing and three methodologically distinct threshold-selection methods, the system stratifies signatures into a five-way confidence-graded classification and quantifies how the practice varies across firms and over time. After further validation, the technology could support financial regulators in screening signature authenticity at national scale.