How do I spot a fake certificate of analysis?

Seven signals

1. No lot number, or one that does not match the vial. The single most common tell.
2. The same certificate across shipments. Certificates are per lot. Reuse means either no per-lot testing or a document being passed off.
3. No issuing laboratory named, or a laboratory with no verifiable existence and no contact route.
4. Summary figures with no chromatogram. The trace is the evidence; the number is the claim.
5. A chromatogram that does not match the claimed purity. Visible unlabeled peaks alongside a 99% figure is a contradiction worth asking about.
6. Typographic inconsistency. Mismatched fonts, misaligned fields, or a compound name spelled differently in different places suggests a document that has been edited.
7. A sterility claim on a purity certificate. Sterility is USP <71>. If it appears in a list beside identity and purity without its own report, something is being conflated or invented.

The one question that settles it

Why fabricated certificates are common here

Purity figures in this category cluster in the same narrow range, so the number carries almost no comparative information and buyers stopped checking it years ago. That makes the document easy to fake and rarely challenged. The defence is not reading the number more carefully. It is verifying the lot and the laboratory, which fabrication cannot survive.

What good practice looks like from the supplier side

• Certificates issued per lot, not per product
• An independent laboratory named, with an accession number on the document
• The chromatogram included rather than summarized
• Measured fill published even when it is under the label quantity
• An honest statement of what is not tested