Verifying your vendor's COA? The free Compound calculator shows mg → mcg → IU on a syringe + half-life graph + cost-per-mcg comparator. RUO context only.
The number
One in five tested vials in the BTLabs survey was mislabeled. The worst case: a retatrutide label on a semaglutide vial. Different molecule. Different half-life. Different math.
That is the headline number out of Bay Test Labs (BTLabs), the independent identity-testing operation whose findings ran in The Hill and propagated through r/saferpeptides over the past quarter. They pulled vials from the unapproved RUO market, ran their own identity tests, and published what they found. Twenty percent miss rate on what was on the label versus what was in the bottle.
That is the number that matters before any of the FDA reclassification fight matters.
Why this matters in two paragraphs
The post-Amino Asylum landscape changed the buyer side of the market. Mastercard's BRAM-11691.1 processor classification quietly tightened payment rails for unapproved peptide sellers; some vendors lost cards entirely, others rerouted through crypto and ACH; the lowest-margin, lowest-QC operators consolidated upstream into the same handful of repackagers. The ecosystem looks the same from the front-end checkout page. The supply chain behind it has compressed.
Operators are now buying more vials from fewer sources. The gray-market vendor concentration risk is at its highest in five years right when the QC layer underneath is most fragmented. That is the structural reason a 20% mislabeling rate is not a one-off fluke. The Certificate of Analysis is the only document that stands between the buyer and whatever the repackager actually put in the box. Most operators have never been taught how to read one. That is the gap.
The 60-second COA-read
A Certificate of Analysis is the document a competent vendor ships (or links to) with each vial. It is the lab report. Not the marketing page. Not the screenshot. The actual report.
Six things sit on a real COA. Each one of them can be a green flag or a red flag. The audit is reading the six in order, ninety seconds end-to-end. Less if you know what you are looking at.
Identity test — was the molecule confirmed, and how?
The identity test is the only line on the COA that tells you what is actually in the vial. Real identity testing is run by mass spectrometry (LC-MS or MALDI-TOF) or by high-performance liquid chromatography with a known reference standard. Good looks like: "Identity confirmed by LC-MS, retention time matches reference standard, observed mass within 0.1% of theoretical." Fail looks like: no method named, only a "yes / pass" stamp, or the test is "appearance and solubility" with no instrumentation behind it. The BTLabs misses are exactly this layer — vials whose identity was never confirmed by an independent instrument.
Purity percentage — was the number measured, and against what threshold?
Purity should be reported as an area-percent figure from the HPLC trace, not a marketing round number. Good looks like: a number with a method ("purity 98.7%, HPLC, 220 nm"), accompanied by the trace itself or a reference to it. Fail looks like: ">99%" with no method, no wavelength, no trace. Reported field practice across practitioner aggregations sits at a >=98% floor for what operators treat as acceptable on injectable RUO peptides; that is the threshold the corpus settles on, not a prescription, and not dosing math. If the number on the COA sits below that floor, the corpus treats the vial as a different category of product.
Date stamp — was this COA run on this batch?
Every COA carries a date of analysis and a batch or lot number. The audit question is: does the batch number on the COA match the batch number printed (or stickered) on the vial in your hand. Good looks like: matching batch, date of analysis within twelve months, lot-specific. Fail looks like: a COA shared across the vendor's whole catalog, no batch number, or a date stamp older than the vial's manufacture date. A recycled COA is the cheapest fraud in the category and the easiest to catch.
Lab credentials — who ran the test, and are they independent?
The COA names the testing lab. The audit question is: is the lab independent of the seller, and is it named at the level of "company, address, signatory" rather than "our QC department." Good looks like: an independent third-party lab with a US or EU address, a contact line, and a named signatory or director. Fail looks like: "internal QC," "in-house lab," or an unnamed entity. BTLabs is itself an example of what a real independent identity lab looks like; the reason their results carry weight is that they have nothing to gain from the vendor's number being right.
Sterility and endotoxin — does it apply, and is the panel run?
For compounds that are reconstituted with bacteriostatic water and pinned, sterility and endotoxin matter. The relevant panels are bioburden / sterility (USP <71> or equivalent) and endotoxin (LAL, USP <85>). Good looks like: both panels named, both passing, both lot-specific. Fail looks like: panels missing, or a generic "passes USP" with no method or pass/fail line item. For oral-only compounds (capsules, troches that are not pinned), this entire row is not load-bearing — read it for completeness, do not weight it the same.
Storage and reconstitution conditions — does the vial state match the COA?
The COA should specify lyophilized or liquid, storage temperature, and shelf life or expiration. The audit question is: does the vial in front of you match. A lyophilized vial with a liquid storage instruction (or vice versa) is a repackaging tell. An expiration date that is missing, or that is months in the past, is its own answer. Reconstitution stability windows live here too — the COA names the bacteriostatic-water reconstitution shelf life, the corpus treats anything outside that window as a degraded vial.
The five most-faked compounds and why
Six categories on the audit. Five compounds where the audit fails most often. Pulled from the cross-channel record (BTLabs survey, r/saferpeptides field reports, the broader vendor-audit thread on r/Peptides).
Retatrutide. The BTLabs case. The price gap between retatrutide and semaglutide is large; the molecules are functionally indistinguishable to the naked eye in lyophilized form; substitution is the highest-margin fraud in the category. This is the reason retatrutide vials sit at the top of the audit-failure list.
Tirzepatide. Same dynamic. Same swap pathway (cheaper GLP-1 substituted under the more expensive label). Compounded tirzepatide also lives inside the active 503(b) regulatory fight, which means the vendor mix is rotating faster than usual.
BPC-157. Different fraud pattern. BPC-157 is cheap to make in low-purity form and expensive to make at the >=98% practitioner floor; the failure mode here is not "wrong molecule," it is "right molecule, low purity, no identity confirmation behind the number on the label."
GHK-Cu. Copper tripeptide; the failure mode is again purity and the copper-binding ratio. Some COAs in the corpus name GHK without specifying whether it is GHK or GHK-Cu, and the binding chemistry is what does the work.
Kisspeptin (or follistatin — flag the early-stage cohort). Both compounds are at the leading edge of the buyer market right now and both are sold with the thinnest QC documentation in the category. They are on this list not because they have been heavily tested by an independent lab, but because the absence of independent testing data on early-stage compounds is itself the failure mode.
The 60-second mental checklist
Three questions to run while looking at a COA on your phone, in order. If any of the three fails, do not pin.
Was the molecule confirmed by mass spec or HPLC, with method and reference standard named on the COA?
Does the batch number on the COA match the batch number on the vial, with a date of analysis inside twelve months?
Is the testing lab named, addressed, and independent of the seller?
If any of these three fails, do not pin.
That is the audit. Sixty seconds with a vial in one hand and the COA on the screen. The other three rows on the full read (purity threshold, sterility/endotoxin panel, storage/reconstitution match) are the deeper layer for operators who want the longer pass. The three above are the floor.
What's next
Next week: After Attia. The trust map for the post-Epstein longevity landscape. Who do you read now.
The CTA
Reply to this email with the worst COA you have ever seen. Photo, paste, or just the punchline. The Brief will publish the worst three (anonymized, with seller details redacted) in a future issue. The corpus is the asset. Your reply is what builds it.
Colby
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For research use only. Not medical advice. Compounds discussed are sold for research purposes; nothing here is a recommendation to use them on humans or animals. The team behind The Compound also operates an RUO peptide vendor; that relationship is disclosed on the about page and applied to every issue under the Conflict Test.