Titles drift; identifiers travel
Romanization, punctuation, translated subtitles, and edition labels vary between stores. A JAN code—the Japanese member system of the global EAN framework—usually offers a stronger matching signal for a packaged retail item. Catalog numbers are especially useful for music, games, and collector editions.
Use a hierarchy of evidence
Start with an official source, record the exact identifier, then match merchant offers against it. If a barcode is absent, combine catalog number, maker, edition, platform, and release date. Title similarity alone is the weakest fallback.
- JAN/EAN or UPC
- Catalog or model number
- Maker + exact edition + release date
- Normalized title only as a final aid
What an identifier cannot prove
A matching code does not prove current stock, price, shipping eligibility, language support, or media rights. Those claims need their own evidence and timestamps. Good catalogue data keeps identity, editorial judgment, and commerce related—but distinct.