I completed a 13,000+ SKU catalog reorganization for a major sports card and collectibles store. The existing data was inconsistent, full of duplicates, and lacked a structured taxonomy. I built a 4-tier Master Taxonomy, created an automated classification rules engine, and ran 119 iterative QA passes (including edge cases and cross-sport collisions). I delivered an import-ready CSV, standardized naming conventions, and a documented ingestion SOP. The image shows a screenshot of the master translation sheet used to map legacy product types to the new 4-tier structure.