A legitimate COA should include: the lab name and contact information, the date of analysis, the peptide identity (confirmed by mass spectrometry), purity percentage (typically via HPLC—look for >95%), and ideally endotoxin and sterility results. Verify the COA by checking that the lab actually exists and performs peptide analysis, that the lot/batch number matches your product, and that the document isn't a recycled template. Vendor-supplied COAs can be fabricated—this is why independent third-party testing through community group buys is strongly recommended.