Independent testing
The question is not only what passed. It is who selected the sample.
A certificate is only as strong as how its sample was chosen. Across the 450 certificates VialGrade aggregates, here is how many were sampled each way. We don’t run these tests — we surface who did and how the sample was obtained.
S1
Vendor selected
The vendor controls which unit reaches the laboratory.
294 on record · 65%
S2
Customer sealed
A customer submits a sealed unit with documented custody.
Not applicable to aggregated COAs
S3
Blind purchase
An independent sampler buys without the seller choosing the unit — the strongest signal.
156 on record · 35%
S4
Multi-source agreement
Separately sourced samples produce consistent observations.
Not applicable to aggregated COAs
What we can say from the corpus
Certificates
450
Blind-tested
156 (35%)
Batch test records
144
Most certificates in any grey-market corpus are vendor-selected — the seller chose the unit. A blind result carries more weight because no one could hand-pick the sample. We label which is which on every certificate rather than treating them as equal.