Testing, certificates and traceability.

Each lot goes through an industry-standard battery at an independent laboratory before release: HPLC for purity, mass spectrometry for identity, and endotoxin screening. The results are recorded on that lot's certificate of analysis. The full methodology is on the quality page.

Yes. Ask for the certificate covering the lot you are being quoted and it arrives with that quote. Certificates are a paid add-on at $75 for each lot, whatever the lot covers; tick the box on the order form to include one per lot, or use the COA request page if you are not ordering yet.

Name the compound and, if you have it, the lot, then use the request page or the notes on your order. Safety data sheets are not charged for — only the certificate of analysis carries a fee.

Every vial carries its lot number, and every certificate names one. What arrives on your dock can be matched line by line against the documentation you were sent for that lot. How to do that matching is in the COA guide.