Vendor verification

How to check if a peptide vendor is legitimate

By The Merit Research Team

To check if a peptide vendor is legitimate, look for independent third-party COAs from a verifiable lab — one you can confirm has a real website and isn't owned or controlled by the vendor. Merit Verified indexes COAs across 100+ vendors and 22 independent labs so you can compare evidence side-by-side.

Six things to check

None of these checks is definitive on its own. Together they build a picture. The single most reliable signal is a pattern of independent COAs from verifiable labs across multiple peptides and lots.

Find an independent COA — not a vendor-produced document

A legitimate vendor will have certificates of analysis issued by an independent third-party laboratory. "Independent" means the lab accepts samples from any source and publishes results it doesn't control. Vendor-produced "in-house" test results or PDFs with no lab letterhead are not COAs — they're marketing materials. Look for a lab name you can Google separately.

Verify the lab is real and not vendor-owned

Search the lab name on its own. A legitimate independent lab has its own website, a physical address, and contact information independent of the vendor. Common independent labs in the peptide space include Janoshik Analytical, Benchmark Analytical (now Analytical Resource Center), and Research Resource Center. If the "lab" only appears in relation to the vendor you're checking, treat it as a red flag.

Match the lot number to current stock

A COA covers a specific production lot, not every vial the vendor has ever sold. Ask the vendor which lot your order ships from and confirm it matches an available COA. A vendor with only one COA from 2022 for a product they claim to continuously stock is a yellow flag.

Look for a pattern of testing across peptides

One COA for one peptide could be a marketing exercise. A vendor with COAs across BPC-157, TB-500, Semaglutide, and BPC-157 from multiple lots shows a routine testing operation. Depth and breadth of independent evidence are hard to fake at scale. Merit Verified surfaces this evidence count on every vendor profile.

Check the regulatory timeline

The FDA reclassified several peptides — including BPC-157, TB-500, and Semaglutide — out of Category 2 compound-ingredient status in April 2025, restricting their compounding. Vendors still openly selling reclassified compounds for "research use" are operating in legal grey territory. This doesn't make the product fake, but it's context you need before deciding.

Cross-reference with an independent registry

Merit Verified maintains a COA registry across 100+ vendors and 22 independent labs. Search any vendor in the directory to see how many COAs are on file, which labs tested them, how recently, and what the measured purity was. A vendor absent from the registry isn't necessarily fake — it may just be newer or untested — but a vendor with no independent evidence anywhere is harder to trust.

What COA evidence actually proves

A COA certifies a tested lot, not your specific vial. Match the batch number on your order to the batch number on the COA. If you can't, the test covers inventory in aggregate — useful as a signal of a vendor's testing practices, but not a certificate for the exact product you received.

Purity is not safety. A COA that reports 99.2% purity for BPC-157 confirms identity and concentration. It does not screen for residual solvents, heavy metals, endotoxins, or microbial contamination. These require separate tests that most vendors don't commission.

Evidence is not an endorsement. Merit Verified surfaces observable verification data — it does not endorse or recommend any vendor. A high Merit Score means accumulated independent COA evidence, not a safety certification or a green light to purchase.

Search vendor directory Browse COA evidence What is a COA?

Frequently asked questions

What is an independent COA for peptides?

An independent COA (Certificate of Analysis) is a test report issued by a third-party laboratory that is not owned or controlled by the vendor. It certifies the identity and purity of a specific peptide lot, including the compound name, lot number, test date, testing method (typically HPLC or HPLC-MS), and measured purity percentage. "Independent" means the lab's results are not controllable by the vendor — any discrepancy between the claim and the measurement would appear in the document regardless of what the vendor wants.

How do I know if a lab that tested a peptide is legitimate?

Search the lab name independently of the vendor. A legitimate independent lab has its own website, a physical address, and testing accreditation (ISO 17025 or CLIA). Labs commonly used for peptide testing include Janoshik Analytical (Czech Republic), Benchmark Analytical / Analytical Resource Center (US), and Research Resource Center. If you can only find the lab mentioned in vendor marketing and nowhere else, treat it as a red flag.

What is the difference between an independent COA and a vendor-produced test?

An independent COA is issued by a lab that the vendor does not own and cannot instruct to alter results. A vendor-produced test is conducted internally or through a lab the vendor controls. Because the vendor controls the output of an in-house test, it provides much weaker evidence of legitimacy. Look for a lab letterhead, lab contact information, and a lab that exists independently of the vendor.

What should I do if a peptide vendor has no independent COAs?

Absence of a COA doesn't prove a vendor is fraudulent — some newer vendors haven't yet accumulated independent test records. But it does mean you have no observable verification evidence. You can ask the vendor directly for a COA, check aggregator databases like Merit Verified to see if any have been submitted, or choose a vendor with existing independent evidence while the new one builds a track record.

Does Merit Verified endorse the vendors it lists?

No. Merit Verified catalogs independent evidence and scores it — it does not endorse, recommend, or certify any vendor. A high Merit Score means a vendor has accumulated substantial independent COA evidence; it is not a safety certificate or a purchasing recommendation. Some vendors with high scores may still carry compounds that are legally restricted for human use.

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