Every manufacturer worth buying from runs release testing on its own batches. The results are usually accurate. The problem is not honesty; it is structure.

Who is asking the question

A release test is run by the party that loses money if the answer is wrong. That does not make it false. It makes it the same category of document as a self-assessment: useful, and not independent, and there is no way to tell the two apart from the outside by reading it.

What a second assay actually adds

• It is run on material that has already traveled. Synthesis-to-release testing happens before shipping; a second assay here happens after, which is the only way to see anything that went wrong in transit.
• It is run on the lot that ships to you, from a sample drawn from it, rather than on a retained sample from the same batch.
• It is run by somebody with no stake in the number. If the two reports disagree, that disagreement is the finding.
• It produces a second document carrying the same lot number, which is what makes comparison possible at all.

The cost, and where it sits

An independent assay runs to a few hundred dollars a lot. Buyers in this market who want one commission it themselves at around three hundred and sixty dollars a time. Here it is already in the unit price, which is a straightforward reason our per-milligram figures are not the lowest on any comparison table you will find.

What happens when they disagree

Occasionally they do, usually by a few tenths of a per cent, which is within what two laboratories and two columns will differ by on the same material. A real divergence is a different matter: the lot does not ship, and if it has already shipped the affected product pages say so.