NSF is a certification reserved for manufacturing facilities only. Because we are a formulator and retailer, but not a manufacturing facility, NSF certification for our products does not apply. Every one of our contracted laboratories has received GMP certification from NSF.
USP certification tests only for purity and potency, not for quality. Although we may consider doing this in the future, in actuality, a product with synthetic Vitamin E - though inferior in biologic activity to the natural and more expensive natural Vitamin E that are used in VisiVite supplements - would "pass" USP certification. The same would issue would arise for products containing "zeaxanthin isomers" rather than the fully biologically potent "dietary zeaxanthin" used in VisiVite.
Our testing methods are far more rigorous than either of these organizations.
We assess not only for purity and potency, but also send to independent laboratories to perform high pressure liquid chromatography analysis of molecular isomers, we test for presence of contaminants and heavy metals, and we routinely perform stability testing to make sure that our products have guaranteed potency beyond the stamped expiration date.
Further Information is available on this page explaining GMP certification.