Amazon.com will have to argue before the Texas Supreme Court about why it shouldn’t be liable for injuries from unsafe products that people buy from third-party sellers that use its marketplace.

The U.S. Court of Appeals for the Fifth Circuit on Dec. 18 certified a question to the Texas high court, asking for an interpretation about whether Amazon meets the definition of a seller under Texas products liability law, or whether it only facilitates commerce between other sellers and buyers. The distinction is key to tell if people can sue the online retailing giant for injuries from products from its platform.