We have written before about how to read a peptide Certificate of Analysis: what HPLC purity means, why mass-spec identity matters, and the red flags of a decorative COA. This article turns the same lens on ourselves. It describes how Cerberus Research Labs documents the lots it supplies, what we publish, what we deliberately do not publish, and where our documentation is still incomplete. It is an educational and transparency piece. It is not medical advice, and nothing here concerns dosing or use. Every compound we supply is for laboratory research use only, not for human or veterinary use.
Two kinds of certificate, labelled as two kinds
Not every COA carries the same weight, and we think a buyer should be able to tell which kind they are looking at without reading the fine print. Our COA library separates them:
- Independent third-party testing. Certificates from an outside laboratory with no stake in the result. At the time of writing, the library lists two of these, both for Retatrutide (15 mg and 30 mg). Where the lab prints a verification ID on the certificate, we show it, so you can check the result directly with that lab rather than trusting our copy.
- Supplier batch certificates. Certificates issued by the manufacturer for an individual batch. These are useful, and they are published unedited, but they are not independent. We label them as batch certificates and do not present them as third-party results.
The distinction matters because "third-party tested" is one of the most overused phrases in this category. If a certificate came from the producer, we call it what it is.
Purity belongs to a lot, not to a compound
You will notice that our product pages do not list a purity percentage. That is intentional. Some properties of a peptide are invariant chemistry: the molecular formula and molecular weight of tirzepatide are the same in every batch ever made. Those we publish on the product page in a Compound Specifications block. Purity is different. It is a measurement of one specific batch, and the next batch on the shelf may measure differently.
Printing "99.4%" as a product attribute would quietly claim that number for whatever stock happens to ship, which may be a different lot entirely. So purity stays where it belongs, on the certificate for the lot it describes, and each product page links to the documentation rather than restating a number out of context. When you see a figure like this on another site with no lot number beside it, it is worth asking which batch it actually describes.
Why a batch number alone is not enough
While indexing our own certificates we found a detail worth sharing with anyone who keeps lot records: supplier batch numbers are not guaranteed to be globally unique. Many are derived from a production date, so two different compounds made on the same day can carry the same batch string. In our own library, a TB-500 certificate and a BPC-157 + Arg certificate share an identical batch number.
The practical lesson for a research lab: key your records on compound + specification (mg per vial) + batch number, never batch number alone. That combination is what our library displays for each certificate where the page states it.
Publishing what we cannot yet name
Part of our certificate archive arrived as full-page scans with no text layer, and some of those scans do not yet have a compound name confirmed to our satisfaction. Rather than guess, the library shows these under "Identification in progress": the page is published exactly as issued, but without a compound label. At the time of writing that section holds 14 pages.
We would rather show you an unlabelled certificate than print a compound name we cannot stand behind. A wrong label on a COA is worse than no label, because it looks like evidence.
The same rule applies to the compound specifications on product pages. Where a value comes from our own certificates, it is read off the certificate. Where we hold no certificate, the reference value is checked against a public chemical database, and we leave the field blank if the database record does not clearly match the compound we supply. Blends and mixtures get no specification table at all, because a mixture has no single molecular formula.
How to get the certificate for your batch
The library shows certificates from recent lots so you can see our documentation before you order. It is a sample of our records, not a promise that every listed certificate matches the stock currently on hand. Product-specific lot status is confirmed during order review, as our documentation page explains. If you want the certificate that matches a specific batch, you can request it before buying or after your order arrives, using the contact details on the COA page.
When it arrives, check it the way you would check anyone's: the batch and specification should match the vial, the date should make sense, and if it claims to be third-party, the lab should be named.
What this documentation does not establish
A certificate of analysis reports identity and purity for a tested lot. It does not establish that a compound is safe, effective, or appropriate for any use. Cerberus Research Labs does not provide dosing guidance, makes no therapeutic or efficacy claims, and does not represent any compound, including Retatrutide, Tirzepatide, BPC-157 or AOD-9604, as suitable for human or veterinary use. These materials are not for human use, and nothing in this article is medical advice.
The short version
We separate independent results from supplier certificates, keep purity on the lot it belongs to, key records on more than a batch number, and leave a field blank rather than fill it with a guess. If you handle lyophilized material in your own lab, our peptide reconstitution calculator covers the concentration arithmetic, and the full research catalog links each compound to its documentation status.