Amazon has changed the requirements for dietary supplements sold on its site.

Supplements are required to meet nutritional labeling laws, as well as cGMPs. Sellers must submit product images and a letter of guarantee from the product manufacturer on official manufacturer letterhead, with assurance that only lawful and safe ingredients are used in concentrations and amounts that are safe for the consumer. Now, sellers must also submit a Certificate of Analysis (COA) backing up the information on the product label. The full list of requirements arehere.

If the requirements are not met, Amazon may remove product listings, suspend sellers, withhold payments, or pursue legal action.

NOW Foods has released a statement applauding the requirements. “The requirement to submit a Certificate of Analysis that verifies those claims, and meets the FDA’s cGMP requirement, is a great step in cleaning up the market,” said Dan Richard, Vice President of Global Sales and Marketing. “It is in the best interest of Amazon and the consumer for Amazon to make it harder for supplement sellers to distribute inferior material.”

Related: NOW Phases Out Use of Magnesium Stearate, Gelatin Capsule What’s Wrong with This Picture? Amazon Business Practice Issues That You Can Take Advantage Of

NOW has testedCoQ10 products, SAMe products,ALAproducts, andPhosphatidyl Serineproducts bought off Amazon, and has found “egregious” problems ranging from unstable material to inaccurate labels, the press release notes. Requiring a COA and requiring products to meet cGMP requirements, NOW says, will help bring these issues under control.

“As a business partner of Amazon, we reported all the quality problems we found to them and asked them to take action,” Richard said. “Assuming there will be a review of all the CofA’s and other provided documents to confirm they are legitimate, this will go a long way in making sure consumers are getting what they expect when they purchase supplements from Amazon.”

NOW has offered Amazon their expertise in evaluating documentation to confirm validity, Richard adds. “We’ve seen all the tactics that cheaters try to get away with, and we’re happy to share our expertise in working together to expel these fringe companies from the marketplace.”