Costco, eBay, Google and the nation's top art museums are backing a Thai graduate student against book publishers, the movie and music industries and other manufacturers in a Supreme Court battle over copyright protections with important implications for consumers and multibillion dollar annual sales online and in discount stores.

Supap Kirtsaeng was studying in the United States when he struck a nerve in the publishing world by tapping into the market for cheaper college textbooks. Kirtsaeng re-sold copyrighted books that relatives first bought abroad.

His profitable venture provoked a copyright infringement lawsuit from publisher John Wiley & Sons. The case is being argued Monday at the high court.

Kirtsaeng used eBay to sell $900,000 worth of books published abroad by Wiley and others and made about $100,000 in profit. The international editions of the textbooks were essentially the same as the more costly American editions. A jury in New York awarded Wiley $600,000 after deciding Kirtsaeng sold copies of eight Wiley textbooks without permission.

The issue at the Supreme Court concerns what protection the holder of a copyright has after a product made outside the United States is sold for the first time. In this case, the issue is whether U.S. copyright protection applies to items that are made abroad, purchased abroad and then resold in the U.S. without the permission of the manufacturer. The high court split 4-4 when it tried to answer that question in a case in 2010 involving Costco and Swiss watch maker Omega.