WASHINGTON – Supreme Court justices are weighing copyright protections for publishers, creative artists and manufacturers in a global marketplace in a case that has attracted the interest of Costco, eBay and Google. The outcome has important implications for consumers and multibillion dollar annual sales online and in discount stores.

In arguments Monday, a book publisher faced off against Supap Kirtsaeng, a Thai graduate student in the U.S. who resold the publisher’s copyrighted books on eBay after relatives first bought nearly identical, cheaper versions abroad.